diff --git a/tests/testsuite/bench.rs b/tests/testsuite/bench.rs
index b7009f6d18b..fff7083e3d8 100644
--- a/tests/testsuite/bench.rs
+++ b/tests/testsuite/bench.rs
@@ -1,5 +1,4 @@
 use support::is_nightly;
-use support::paths::CargoPathExt;
 use support::{basic_bin_manifest, basic_lib_manifest, basic_manifest, project};
 
 #[test]
@@ -13,22 +12,23 @@ fn cargo_bench_simple() {
         .file(
             "src/main.rs",
             r#"
-            #![feature(test)]
-            #[cfg(test)]
-            extern crate test;
-
-            fn hello() -> &'static str {
-                "hello"
-            }
-
-            pub fn main() {
-                println!("{}", hello())
-            }
-
-            #[bench]
-            fn bench_hello(_b: &mut test::Bencher) {
-                assert_eq!(hello(), "hello")
-            }"#,
+                #![feature(test)]
+                #[cfg(test)]
+                extern crate test;
+
+                fn hello() -> &'static str {
+                    "hello"
+                }
+
+                pub fn main() {
+                    println!("{}", hello())
+                }
+
+                #[bench]
+                fn bench_hello(_b: &mut test::Bencher) {
+                    assert_eq!(hello(), "hello")
+                }
+            "#,
         ).build();
 
     p.cargo("build").run();
@@ -42,7 +42,8 @@ fn cargo_bench_simple() {
 [COMPILING] foo v0.5.0 (CWD)
 [FINISHED] release [optimized] target(s) in [..]
 [RUNNING] target/release/deps/foo-[..][EXE]",
-        ).with_stdout_contains("test bench_hello ... bench: [..]")
+        )
+        .with_stdout_contains("test bench_hello ... bench: [..]")
         .run();
 }
 
@@ -844,7 +845,7 @@ fn bench_dylib() {
         return;
     }
 
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -913,7 +914,7 @@ fn bench_dylib() {
         ).with_stdout_contains_n("test foo ... bench: [..]", 2)
         .run();
 
-    p.root().move_into_the_past();
+    p.write_file("foo", "bar");
     p.cargo("bench -v")
         .with_stderr(
             "\
diff --git a/tests/testsuite/build.rs b/tests/testsuite/build.rs
index 7c0d4245a5e..b9cad7f2270 100644
--- a/tests/testsuite/build.rs
+++ b/tests/testsuite/build.rs
@@ -1,13 +1,15 @@
 use std::env;
 use std::fs::{self, File};
 use std::io::prelude::*;
+use std::thread;
+use std::time::Duration;
 
 use cargo::util::paths::dylib_path_envvar;
 use support::paths::{root, CargoPathExt};
 use support::registry::Package;
 use support::ProjectBuilder;
 use support::{
-    basic_bin_manifest, basic_lib_manifest, basic_manifest, is_nightly, rustc_host, sleep_ms,
+    basic_bin_manifest, basic_lib_manifest, basic_manifest, is_nightly, rustc_host,
 };
 use support::{main_file, project, Execs};
 
@@ -1986,7 +1988,7 @@ fn inferred_main_bin() {
 
 #[test]
 fn deletion_causes_failure() {
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -2004,7 +2006,7 @@ fn deletion_causes_failure() {
         .build();
 
     p.cargo("build").run();
-    p.change_file("Cargo.toml", &basic_manifest("foo", "0.0.1"));
+    p.write_file("Cargo.toml", &basic_manifest("foo", "0.0.1"));
     p.cargo("build").with_status(101).run();
 }
 
@@ -2123,7 +2125,7 @@ fn single_lib() {
 
 #[test]
 fn freshness_ignores_excluded() {
-    let foo = project()
+    let mut foo = project()
         .file(
             "Cargo.toml",
             r#"
@@ -2137,7 +2139,6 @@ fn freshness_ignores_excluded() {
         ).file("build.rs", "fn main() {}")
         .file("src/lib.rs", "pub fn bar() -> i32 { 1 }")
         .build();
-    foo.root().move_into_the_past();
 
     foo.cargo("build")
         .with_stderr(
@@ -2149,17 +2150,17 @@ fn freshness_ignores_excluded() {
 
     // Smoke test to make sure it doesn't compile again
     println!("first pass");
-    foo.cargo("build").with_stdout("").run();
+    foo.cargo("build").with_stderr("[FINISHED] [..]\n").run();
 
     // Modify an ignored file and make sure we don't rebuild
     println!("second pass");
-    File::create(&foo.root().join("src/bar.rs")).unwrap();
-    foo.cargo("build").with_stdout("").run();
+    foo.write_file("src/bar.rs", "");
+    foo.cargo("build").with_stderr("[FINISHED] [..]\n").run();
 }
 
 #[test]
 fn rebuild_preserves_out_dir() {
-    let foo = project()
+    let mut foo = project()
         .file(
             "Cargo.toml",
             r#"
@@ -2187,7 +2188,6 @@ fn rebuild_preserves_out_dir() {
         "#,
         ).file("src/lib.rs", "pub fn bar() -> i32 { 1 }")
         .build();
-    foo.root().move_into_the_past();
 
     foo.cargo("build")
         .env("FIRST", "1")
@@ -2198,7 +2198,7 @@ fn rebuild_preserves_out_dir() {
 ",
         ).run();
 
-    File::create(&foo.root().join("src/bar.rs")).unwrap();
+    foo.write_file("src/bar.rs", "");
     foo.cargo("build")
         .with_stderr(
             "\
@@ -2247,8 +2247,7 @@ fn recompile_space_in_name() {
         ).file("src/my lib.rs", "")
         .build();
     foo.cargo("build").run();
-    foo.root().move_into_the_past();
-    foo.cargo("build").with_stdout("").run();
+    foo.cargo("build").with_stderr("[FINISHED] [..]\n").run();
 }
 
 #[cfg(unix)]
@@ -2524,7 +2523,7 @@ fn compile_then_delete() {
     assert!(p.bin("foo").is_file());
     if cfg!(windows) {
         // On windows unlinking immediately after running often fails, so sleep
-        sleep_ms(100);
+        thread::sleep(Duration::from_millis(100));
     }
     fs::remove_file(&p.bin("foo")).unwrap();
     p.cargo("run -v").run();
diff --git a/tests/testsuite/build_script.rs b/tests/testsuite/build_script.rs
index 6b4382437d5..fb247e3a718 100644
--- a/tests/testsuite/build_script.rs
+++ b/tests/testsuite/build_script.rs
@@ -9,7 +9,7 @@ use cargo::util::paths::remove_dir_all;
 use support::paths::CargoPathExt;
 use support::registry::Package;
 use support::{basic_manifest, cross_compile, project};
-use support::{rustc_host, sleep_ms};
+use support::rustc_host;
 
 #[test]
 fn custom_build_script_failed() {
@@ -528,7 +528,7 @@ fn links_passes_env_vars() {
 
 #[test]
 fn only_rerun_build_script() {
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -543,10 +543,8 @@ fn only_rerun_build_script() {
         .build();
 
     p.cargo("build -v").run();
-    p.root().move_into_the_past();
 
-    File::create(&p.root().join("some-new-file")).unwrap();
-    p.root().move_into_the_past();
+    p.write_file("some-new-file", "");
 
     p.cargo("build -v")
         .with_stderr(
@@ -585,9 +583,8 @@ fn rebuild_continues_to_pass_env_vars() {
             }
         "#,
         ).build();
-    a.root().move_into_the_past();
 
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             &format!(
@@ -616,17 +613,15 @@ fn rebuild_continues_to_pass_env_vars() {
         ).build();
 
     p.cargo("build -v").run();
-    p.root().move_into_the_past();
 
-    File::create(&p.root().join("some-new-file")).unwrap();
-    p.root().move_into_the_past();
+    p.write_file("some-new-file", "");
 
     p.cargo("build -v").run();
 }
 
 #[test]
 fn testing_and_such() {
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -642,10 +637,8 @@ fn testing_and_such() {
 
     println!("build");
     p.cargo("build -v").run();
-    p.root().move_into_the_past();
 
-    File::create(&p.root().join("src/lib.rs")).unwrap();
-    p.root().move_into_the_past();
+    p.write_file("src/lib.rs", "");
 
     println!("test");
     p.cargo("test -vj1")
@@ -672,10 +665,7 @@ fn testing_and_such() {
 ",
         ).run();
 
-    File::create(&p.root().join("src/main.rs"))
-        .unwrap()
-        .write_all(b"fn main() {}")
-        .unwrap();
+    p.write_file("src/main.rs", "fn main() {}");
     println!("run");
     p.cargo("run")
         .with_stderr(
@@ -979,7 +969,7 @@ fn build_cmd_with_a_build_cmd() {
 
 #[test]
 fn out_dir_is_preserved() {
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -1005,29 +995,27 @@ fn out_dir_is_preserved() {
 
     // Make the file
     p.cargo("build -v").run();
-    p.root().move_into_the_past();
 
     // Change to asserting that it's there
-    File::create(&p.root().join("build.rs"))
-        .unwrap()
-        .write_all(
-            br#"
-        use std::env;
-        use std::old_io::File;
-        fn main() {
-            let out = env::var("OUT_DIR").unwrap();
-            File::open(&Path::new(&out).join("foo")).unwrap();
-        }
-    "#,
-        ).unwrap();
-    p.root().move_into_the_past();
+    p.write_file(
+        "build.rs",
+        r#"
+            use std::env;
+            use std::fs::File;
+            use std::path::Path;
+            fn main() {
+                let out = env::var("OUT_DIR").unwrap();
+                File::open(&Path::new(&out).join("foo")).unwrap();
+            }
+        "#,
+    );
     p.cargo("build -v").run();
 
     // Run a fresh build where file should be preserved
     p.cargo("build -v").run();
 
     // One last time to make sure it's still there.
-    File::create(&p.root().join("foo")).unwrap();
+    p.write_file("foo", "");
     p.cargo("build -v").run();
 }
 
@@ -1455,12 +1443,10 @@ fn build_script_with_dynamic_native_dependency() {
 
     build
         .cargo("build -v")
-        .env("RUST_LOG", "cargo::ops::cargo_rustc")
         .run();
 
     foo.cargo("build -v")
         .env("SRC", build.root())
-        .env("RUST_LOG", "cargo::ops::cargo_rustc")
         .run();
 }
 
@@ -2248,7 +2234,6 @@ fn fresh_builds_possible_with_link_libs() {
         ).run();
 
     p.cargo("build -v")
-        .env("RUST_LOG", "cargo::ops::cargo_rustc::fingerprint=info")
         .with_stderr(
             "\
 [FRESH] foo v0.5.0 ([..])
@@ -2299,7 +2284,6 @@ fn fresh_builds_possible_with_multiple_metadata_overrides() {
         ).run();
 
     p.cargo("build -v")
-        .env("RUST_LOG", "cargo::ops::cargo_rustc::fingerprint=info")
         .with_stderr(
             "\
 [FRESH] foo v0.5.0 ([..])
@@ -2310,7 +2294,12 @@ fn fresh_builds_possible_with_multiple_metadata_overrides() {
 
 #[test]
 fn rebuild_only_on_explicit_paths() {
-    let p = project()
+    let sleep = || {
+        use std::thread;
+        use std::time::Duration;
+        thread::sleep(Duration::new(1, 0));
+    };
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -2330,6 +2319,7 @@ fn rebuild_only_on_explicit_paths() {
             }
         "#,
         ).build();
+    p.disable_mtime_management(); // TODO: should fix this test a different way...
 
     p.cargo("build -v").run();
 
@@ -2345,10 +2335,10 @@ fn rebuild_only_on_explicit_paths() {
 ",
         ).run();
 
-    sleep_ms(1000);
-    File::create(p.root().join("foo")).unwrap();
-    File::create(p.root().join("bar")).unwrap();
-    sleep_ms(1000); // make sure the to-be-created outfile has a timestamp distinct from the infiles
+    sleep();
+    p.write_file("foo", "");
+    p.write_file("bar", "");
+    sleep();
 
     // now the exist, so run once, catch the mtime, then shouldn't run again
     println!("run with");
@@ -2371,11 +2361,11 @@ fn rebuild_only_on_explicit_paths() {
 ",
         ).run();
 
-    sleep_ms(1000);
+    sleep();
 
     // random other files do not affect freshness
     println!("run baz");
-    File::create(p.root().join("baz")).unwrap();
+    p.write_file("baz", "");
     p.cargo("build -v")
         .with_stderr(
             "\
@@ -2386,7 +2376,7 @@ fn rebuild_only_on_explicit_paths() {
 
     // but changing dependent files does
     println!("run foo change");
-    File::create(p.root().join("foo")).unwrap();
+    p.write_file("foo", "");
     p.cargo("build -v")
         .with_stderr(
             "\
@@ -3257,7 +3247,7 @@ fn rename_with_link_search_path() {
             }
         "#,
         );
-    let p2 = p2.build();
+    let mut p2 = p2.build();
 
     // Move the output `libfoo.so` into the directory of `p2`, and then delete
     // the `p` project. On OSX the `libfoo.dylib` artifact references the
@@ -3306,6 +3296,7 @@ fn rename_with_link_search_path() {
         println!("assuming {} is spurious, waiting to try again", error);
         thread::sleep(Duration::from_millis(100));
     }
+    p2.set_root(&new);
 
     p2.cargo("run")
         .cwd(&new)
diff --git a/tests/testsuite/build_script_env.rs b/tests/testsuite/build_script_env.rs
index 2a7be1aa564..e1305ba4186 100644
--- a/tests/testsuite/build_script_env.rs
+++ b/tests/testsuite/build_script_env.rs
@@ -1,7 +1,4 @@
-use std::fs::File;
-
 use support::project;
-use support::sleep_ms;
 
 #[test]
 fn rerun_if_env_changes() {
@@ -54,7 +51,7 @@ fn rerun_if_env_changes() {
 
 #[test]
 fn rerun_if_env_or_file_changes() {
-    let p = project()
+    let mut p = project()
         .file("src/main.rs", "fn main() {}")
         .file(
             "build.rs",
@@ -86,8 +83,7 @@ fn rerun_if_env_or_file_changes() {
         .env("FOO", "bar")
         .with_stderr("[FINISHED] [..]")
         .run();
-    sleep_ms(1000);
-    File::create(p.root().join("foo")).unwrap();
+    p.write_file("foo", "");
     p.cargo("build")
         .env("FOO", "bar")
         .with_stderr(
diff --git a/tests/testsuite/features.rs b/tests/testsuite/features.rs
index eaca5b1d94a..6c4d6ead5bc 100644
--- a/tests/testsuite/features.rs
+++ b/tests/testsuite/features.rs
@@ -1,7 +1,6 @@
 use std::fs::File;
 use std::io::prelude::*;
 
-use support::paths::CargoPathExt;
 use support::registry::Package;
 use support::{basic_manifest, project};
 
@@ -101,7 +100,7 @@ Consider adding `optional = true` to the dependency
 
 #[test]
 fn invalid4() {
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -133,7 +132,7 @@ the package `foo` depends on `bar`, with features: `bar` but `bar` does not have
 failed to select a version for `bar` which could resolve this conflict",
         ).run();
 
-    p.change_file("Cargo.toml", &basic_manifest("foo", "0.0.1"));
+    p.write_file("Cargo.toml", &basic_manifest("foo", "0.0.1"));
 
     p.cargo("build --features test")
         .with_status(101)
@@ -747,8 +746,8 @@ fn many_features_no_rebuilds() {
 [COMPILING] b v0.1.0 (CWD)
 [FINISHED] dev [unoptimized + debuginfo] target(s) in [..]
 ",
-        ).run();
-    p.root().move_into_the_past();
+        )
+        .run();
 
     p.cargo("build -v")
         .with_stderr(
diff --git a/tests/testsuite/freshness.rs b/tests/testsuite/freshness.rs
index f450cdb6c9d..db3e80de0a5 100644
--- a/tests/testsuite/freshness.rs
+++ b/tests/testsuite/freshness.rs
@@ -1,14 +1,14 @@
 use std::fs::{self, File};
 use std::io::prelude::*;
 
-use support::paths::CargoPathExt;
+use filetime::{self, FileTime};
+
 use support::registry::Package;
-use support::sleep_ms;
 use support::{basic_manifest, project};
 
 #[test]
 fn modifying_and_moving() {
-    let p = project()
+    let mut p = project()
         .file("src/main.rs", "mod a; fn main() {}")
         .file("src/a.rs", "")
         .build();
@@ -22,13 +22,8 @@ fn modifying_and_moving() {
         ).run();
 
     p.cargo("build").with_stdout("").run();
-    p.root().move_into_the_past();
-    p.root().join("target").move_into_the_past();
 
-    File::create(&p.root().join("src/a.rs"))
-        .unwrap()
-        .write_all(b"#[allow(unused)]fn main() {}")
-        .unwrap();
+    p.write_file("src/a.rs", "#[allow(unused)] fn main() {}");
     p.cargo("build")
         .with_stderr(
             "\
@@ -37,13 +32,14 @@ fn modifying_and_moving() {
 ",
         ).run();
 
-    fs::rename(&p.root().join("src/a.rs"), &p.root().join("src/b.rs")).unwrap();
+    p.write_file("src/b.rs", "");
+    fs::remove_file(p.root().join("src/a.rs")).unwrap();
     p.cargo("build").with_status(101).run();
 }
 
 #[test]
 fn modify_only_some_files() {
-    let p = project()
+    let mut p = project()
         .file("src/lib.rs", "mod a;")
         .file("src/a.rs", "")
         .file("src/main.rs", "mod b; fn main() {}")
@@ -59,22 +55,14 @@ fn modify_only_some_files() {
 ",
         ).run();
     p.cargo("test").run();
-    sleep_ms(1000);
 
     assert!(p.bin("foo").is_file());
 
-    let lib = p.root().join("src/lib.rs");
-    let bin = p.root().join("src/b.rs");
+    // we shouldn't recompile the library
+    fs::write(p.root().join("src/lib.rs"), "invalid rust code").unwrap();
 
-    File::create(&lib)
-        .unwrap()
-        .write_all(b"invalid rust code")
-        .unwrap();
-    File::create(&bin)
-        .unwrap()
-        .write_all(b"#[allow(unused)]fn foo() {}")
-        .unwrap();
-    lib.move_into_the_past();
+    // but we should recompile the binary
+    p.write_file("src/b.rs", "#[allow(unused)] fn foo() {}");
 
     // Make sure the binary is rebuilt, not the lib
     p.cargo("build")
@@ -462,7 +450,7 @@ fn changing_bin_features_caches_targets() {
 
 #[test]
 fn rebuild_tests_if_lib_changes() {
-    let p = project()
+    let mut p = project()
         .file("src/lib.rs", "pub fn foo() {}")
         .file(
             "tests/foo.rs",
@@ -476,8 +464,7 @@ fn rebuild_tests_if_lib_changes() {
     p.cargo("build").run();
     p.cargo("test").run();
 
-    sleep_ms(1000);
-    File::create(&p.root().join("src/lib.rs")).unwrap();
+    p.write_file("src/lib.rs", "");
 
     p.cargo("build -v").run();
     p.cargo("test -v").with_status(101).run();
@@ -680,7 +667,11 @@ fn no_rebuild_if_build_artifacts_move_backwards_in_time() {
 
     p.cargo("build").run();
 
-    p.root().move_into_the_past();
+    filetime::set_file_times(
+        p.root().join("src/lib.rs"),
+        FileTime::from_unix_time(0, 0),
+        FileTime::from_unix_time(0, 0),
+    ).unwrap();
 
     p.cargo("build")
         .with_stdout("")
@@ -690,29 +681,29 @@ fn no_rebuild_if_build_artifacts_move_backwards_in_time() {
 
 #[test]
 fn rebuild_if_build_artifacts_move_forward_in_time() {
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
-            [package]
-            name = "foo"
-            version = "0.0.1"
-            authors = []
+                [package]
+                name = "foo"
+                version = "0.0.1"
+                authors = []
 
-            [dependencies]
-            a = { path = "a" }
-        "#,
-        ).file("src/lib.rs", "")
+                [dependencies]
+                a = { path = "a" }
+            "#,
+        )
+        .file("src/lib.rs", "")
         .file("a/Cargo.toml", &basic_manifest("a", "0.0.1"))
         .file("a/src/lib.rs", "")
         .build();
 
     p.cargo("build").run();
 
-    p.root().move_into_the_future();
+    p.write_file("a/src/lib.rs", "");
 
     p.cargo("build")
-        .env("RUST_LOG", "")
         .with_stdout("")
         .with_stderr(
             "\
@@ -779,7 +770,7 @@ fn rebuild_if_environment_changes() {
 
 #[test]
 fn no_rebuild_when_rename_dir() {
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -801,9 +792,9 @@ fn no_rebuild_when_rename_dir() {
     new.pop();
     new.push("bar");
     fs::rename(p.root(), &new).unwrap();
+    p.set_root(&new);
 
     p.cargo("build")
-        .cwd(&new)
         .with_stderr("[FINISHED] dev [unoptimized + debuginfo] target(s) in [..]")
         .run();
 }
diff --git a/tests/testsuite/git.rs b/tests/testsuite/git.rs
index c99f5839e06..58e4c148495 100644
--- a/tests/testsuite/git.rs
+++ b/tests/testsuite/git.rs
@@ -1,6 +1,6 @@
 use git2;
 use std::env;
-use std::fs::{self, File};
+use std::fs::File;
 use std::io::prelude::*;
 use std::net::{TcpListener, TcpStream};
 use std::path::Path;
@@ -8,8 +8,7 @@ use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::Arc;
 use std::thread;
 
-use support::paths::{self, CargoPathExt};
-use support::sleep_ms;
+use support::paths;
 use support::{basic_lib_manifest, basic_manifest, git, main_file, path2url, project};
 
 #[test]
@@ -756,7 +755,6 @@ fn recompilation() {
 
     println!("compile after commit");
     p.cargo("build").with_stdout("").run();
-    p.root().move_into_the_past();
 
     // Update the dependency and carry on!
     p.cargo("update")
@@ -874,8 +872,6 @@ fn update_with_shared_deps() {
     git::add(&repo);
     git::commit(&repo);
 
-    sleep_ms(1000);
-
     // By default, not transitive updates
     println!("dep1 update");
     p.cargo("update -p dep1").with_stdout("").run();
@@ -1164,8 +1160,6 @@ fn stale_cached_version() {
     git::add(&repo);
     git::commit(&repo);
 
-    sleep_ms(1000);
-
     let rev = repo.revparse_single("HEAD").unwrap().id();
 
     File::create(&foo.root().join("Cargo.lock"))
@@ -1286,7 +1280,6 @@ fn dep_with_changed_submodule() {
     git::add(&repo);
     git::commit(&repo);
 
-    sleep_ms(1000);
     // Update the dependency and carry on!
     println!("update");
     p.cargo("update -v")
@@ -1395,9 +1388,6 @@ fn git_build_cmd_freshness() {
             .file("src/lib.rs", "pub fn bar() -> i32 { 1 }")
             .file(".gitignore", "src/bar.rs")
     }).unwrap();
-    foo.root().move_into_the_past();
-
-    sleep_ms(1000);
 
     foo.cargo("build")
         .with_stderr(
@@ -1494,7 +1484,6 @@ fn git_repo_changing_no_rebuild() {
         ).file("src/main.rs", "fn main() {}")
         .file("build.rs", "fn main() {}")
         .build();
-    p1.root().move_into_the_past();
     p1.cargo("build")
         .with_stderr(&format!(
             "\
@@ -1551,7 +1540,7 @@ fn git_repo_changing_no_rebuild() {
 
 #[test]
 fn git_dep_build_cmd() {
-    let p = git::new("foo", |project| {
+    let mut p = git::new("foo", |project| {
         project
             .file(
                 "Cargo.toml",
@@ -1602,17 +1591,12 @@ fn git_dep_build_cmd() {
             )
     }).unwrap();
 
-    p.root().join("bar").move_into_the_past();
-
     p.cargo("build").run();
 
     p.process(&p.bin("foo")).with_stdout("0\n").run();
 
     // Touching bar.rs.in should cause the `build` command to run again.
-    fs::File::create(&p.root().join("bar/src/bar.rs.in"))
-        .unwrap()
-        .write_all(b"pub fn gimme() -> i32 { 1 }")
-        .unwrap();
+    p.write_file("bar/src/bar.rs.in", "pub fn gimme() -> i32 { 1 }");
 
     p.cargo("build").run();
 
@@ -2385,7 +2369,6 @@ fn include_overrides_gitignore() {
         ).run();
 
     println!("build 3: touch `src/not_incl.rs`; expect build script *not* re-run");
-    sleep_ms(1000);
     File::create(p.root().join("src").join("not_incl.rs")).unwrap();
 
     p.cargo("build -v")
@@ -2403,7 +2386,6 @@ fn include_overrides_gitignore() {
     // explicitly included file should cause a build-script re-run,
     // even if that same file is matched by `.gitignore`.
     println!("build 4: touch `src/incl.rs`; expect build script re-run");
-    sleep_ms(1000);
     File::create(p.root().join("src").join("incl.rs")).unwrap();
 
     p.cargo("build -v")
diff --git a/tests/testsuite/out_dir.rs b/tests/testsuite/out_dir.rs
index 2700e528d2c..e64074195dd 100644
--- a/tests/testsuite/out_dir.rs
+++ b/tests/testsuite/out_dir.rs
@@ -2,7 +2,6 @@ use std::env;
 use std::fs::{self, File};
 use std::path::Path;
 
-use support::sleep_ms;
 use support::{basic_manifest, project};
 
 #[test]
@@ -177,7 +176,7 @@ fn out_dir_is_a_file() {
 
 #[test]
 fn replaces_artifacts() {
-    let p = project()
+    let mut p = project()
         .file("src/main.rs", r#"fn main() { println!("foo") }"#)
         .build();
 
@@ -190,8 +189,7 @@ fn replaces_artifacts() {
     ).with_stdout("foo")
     .run();
 
-    sleep_ms(1000);
-    p.change_file("src/main.rs", r#"fn main() { println!("bar") }"#);
+    p.write_file("src/main.rs", r#"fn main() { println!("bar") }"#);
 
     p.cargo("build -Z unstable-options --out-dir out")
         .masquerade_as_nightly_cargo()
diff --git a/tests/testsuite/package.rs b/tests/testsuite/package.rs
index 3a8503c7d06..f6e1551a6c9 100644
--- a/tests/testsuite/package.rs
+++ b/tests/testsuite/package.rs
@@ -7,7 +7,7 @@ use flate2::read::GzDecoder;
 use git2;
 use support::registry::Package;
 use support::{basic_manifest, git, is_nightly, path2url, paths, project, registry};
-use support::{cargo_process, sleep_ms};
+use support::cargo_process;
 use tar::Archive;
 
 #[test]
@@ -691,7 +691,7 @@ Caused by:
 
 #[test]
 fn do_not_package_if_repository_is_dirty() {
-    let p = project().build();
+    let mut p = project().build();
 
     // Create a Git repository containing a minimal Rust project.
     let _ = git::repo(&paths::root().join("foo"))
@@ -711,7 +711,7 @@ fn do_not_package_if_repository_is_dirty() {
         .build();
 
     // Modify Cargo.toml without committing the change.
-    p.change_file(
+    p.write_file(
         "Cargo.toml",
         r#"
             [project]
@@ -1257,7 +1257,7 @@ fn lock_file_and_workspace() {
 
 #[test]
 fn do_not_package_if_src_was_modified() {
-    let p = project()
+    let mut p = project()
         .file("src/main.rs", r#"fn main() { println!("hello"); }"#)
         .file(
             "build.rs",
@@ -1270,14 +1270,13 @@ fn do_not_package_if_src_was_modified() {
                 file.write_all(b"Hello, world of generated files.").expect("failed to write");
             }
         "#,
-        ).build();
+        )
+        .build();
 
-    if cfg!(target_os = "macos") {
-        // MacOS has 1s resolution filesystem.
-        // If src/main.rs is created within 1s of src/generated.txt, then it
-        // won't trigger the modification check.
-        sleep_ms(1000);
-    }
+    // MacOS has 1s resolution filesystem.
+    // If src/main.rs is created within 1s of src/generated.txt, then it
+    // won't trigger the modification check.
+    p.move_start_back_one_second();
 
     p.cargo("package")
         .with_status(101)
diff --git a/tests/testsuite/path.rs b/tests/testsuite/path.rs
index 42f6e8ceb53..9de84caf671 100644
--- a/tests/testsuite/path.rs
+++ b/tests/testsuite/path.rs
@@ -1,9 +1,8 @@
 use std::fs::{self, File};
 use std::io::prelude::*;
 
-use support::paths::{self, CargoPathExt};
+use support::paths;
 use support::registry::Package;
-use support::sleep_ms;
 use support::{basic_lib_manifest, basic_manifest, main_file, project};
 
 #[test]
@@ -236,7 +235,7 @@ fn cargo_compile_with_transitive_dev_deps() {
 
 #[test]
 fn no_rebuild_dependency() {
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -253,6 +252,7 @@ fn no_rebuild_dependency() {
         .file("bar/Cargo.toml", &basic_lib_manifest("bar"))
         .file("bar/src/bar.rs", "pub fn bar() {}")
         .build();
+
     // First time around we should compile both foo and bar
     p.cargo("build")
         .with_stderr(
@@ -262,14 +262,14 @@ fn no_rebuild_dependency() {
              in [..]\n",
         ).run();
 
-    sleep_ms(1000);
-    p.change_file(
+    p.write_file(
         "src/main.rs",
         r#"
-        extern crate bar;
-        fn main() { bar::bar(); }
-    "#,
+            extern crate bar;
+            fn main() { bar::bar(); }
+        "#,
     );
+
     // Don't compile bar, but do recompile foo.
     p.cargo("build")
         .with_stderr(
@@ -282,40 +282,49 @@ fn no_rebuild_dependency() {
 
 #[test]
 fn deep_dependencies_trigger_rebuild() {
-    let p = project()
+    let sleep = || {
+        use std::thread;
+        use std::time::Duration;
+        thread::sleep(Duration::new(1, 0));
+    };
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
-            [project]
+                [project]
 
-            name = "foo"
-            version = "0.5.0"
-            authors = ["wycats@example.com"]
+                name = "foo"
+                version = "0.5.0"
+                authors = ["wycats@example.com"]
 
-            [dependencies.bar]
-            path = "bar"
-        "#,
-        ).file("src/main.rs", "extern crate bar; fn main() { bar::bar() }")
+                [dependencies.bar]
+                path = "bar"
+            "#,
+        )
+        .file("src/main.rs", "extern crate bar; fn main() { bar::bar() }")
         .file(
             "bar/Cargo.toml",
             r#"
-            [project]
+                [project]
 
-            name = "bar"
-            version = "0.5.0"
-            authors = ["wycats@example.com"]
+                name = "bar"
+                version = "0.5.0"
+                authors = ["wycats@example.com"]
 
-            [lib]
-            name = "bar"
-            [dependencies.baz]
-            path = "../baz"
-        "#,
-        ).file(
+                [lib]
+                name = "bar"
+                [dependencies.baz]
+                path = "../baz"
+            "#,
+        )
+        .file(
             "bar/src/bar.rs",
             "extern crate baz; pub fn bar() { baz::baz() }",
-        ).file("baz/Cargo.toml", &basic_lib_manifest("baz"))
+        )
+        .file("baz/Cargo.toml", &basic_lib_manifest("baz"))
         .file("baz/src/baz.rs", "pub fn baz() {}")
         .build();
+    p.disable_mtime_management();
     p.cargo("build")
         .with_stderr(
             "[COMPILING] baz v0.5.0 (CWD/baz)\n\
@@ -327,14 +336,9 @@ fn deep_dependencies_trigger_rebuild() {
     p.cargo("build").with_stdout("").run();
 
     // Make sure an update to baz triggers a rebuild of bar
-    //
-    // We base recompilation off mtime, so sleep for at least a second to ensure
-    // that this write will change the mtime.
-    File::create(&p.root().join("baz/src/baz.rs"))
-        .unwrap()
-        .write_all(br#"pub fn baz() { println!("hello!"); }"#)
-        .unwrap();
-    sleep_ms(1000);
+    sleep();
+    p.write_file("baz/src/baz.rs", "pub fn baz() {}");
+
     p.cargo("build")
         .with_stderr(
             "[COMPILING] baz v0.5.0 (CWD/baz)\n\
@@ -345,22 +349,22 @@ fn deep_dependencies_trigger_rebuild() {
         ).run();
 
     // Make sure an update to bar doesn't trigger baz
-    File::create(&p.root().join("bar/src/bar.rs"))
-        .unwrap()
-        .write_all(
-            br#"
-        extern crate baz;
-        pub fn bar() { println!("hello!"); baz::baz(); }
-    "#,
-        ).unwrap();
-    sleep_ms(1000);
+    sleep();
+    p.write_file(
+        "bar/src/bar.rs",
+        r#"
+            extern crate baz;
+            pub fn bar() { println!("hello!"); baz::baz(); }
+        "#,
+    );
     p.cargo("build")
         .with_stderr(
             "[COMPILING] bar v0.5.0 (CWD/bar)\n\
              [COMPILING] foo v0.5.0 (CWD)\n\
              [FINISHED] dev [unoptimized + debuginfo] target(s) \
              in [..]\n",
-        ).run();
+        )
+        .run();
 }
 
 #[test]
@@ -414,7 +418,7 @@ fn no_rebuild_two_deps() {
 
 #[test]
 fn nested_deps_recompile() {
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -440,13 +444,10 @@ fn nested_deps_recompile() {
              [COMPILING] foo v0.5.0 (CWD)\n\
              [FINISHED] dev [unoptimized + debuginfo] target(s) \
              in [..]\n",
-        ).run();
-    sleep_ms(1000);
+        )
+        .run();
 
-    File::create(&p.root().join("src/main.rs"))
-        .unwrap()
-        .write_all(br#"fn main() {}"#)
-        .unwrap();
+    p.write_file("src/main.rs", "fn main() {}");
 
     // This shouldn't recompile `bar`
     p.cargo("build")
@@ -617,7 +618,7 @@ fn override_path_dep() {
 
 #[test]
 fn path_dep_build_cmd() {
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -657,7 +658,6 @@ fn path_dep_build_cmd() {
         "#,
         ).file("bar/src/bar.rs.in", "pub fn gimme() -> i32 { 0 }")
         .build();
-    p.root().join("bar").move_into_the_past();
 
     p.cargo("build")
         .with_stderr(
@@ -672,12 +672,7 @@ fn path_dep_build_cmd() {
     p.process(&p.bin("foo")).with_stdout("0\n").run();
 
     // Touching bar.rs.in should cause the `build` command to run again.
-    {
-        let file = fs::File::create(&p.root().join("bar/src/bar.rs.in"));
-        file.unwrap()
-            .write_all(br#"pub fn gimme() -> i32 { 1 }"#)
-            .unwrap();
-    }
+    p.write_file("bar/src/bar.rs.in", "pub fn gimme() -> i32 { 1 } ");
 
     p.cargo("build")
         .with_stderr(
@@ -775,11 +770,12 @@ fn custom_target_no_rebuild() {
 ",
         ).run();
 
+    let mut cargo = p.cargo("build --manifest-path=b/Cargo.toml");
     t!(fs::rename(
         p.root().join("target"),
         p.root().join("target_moved")
     ));
-    p.cargo("build --manifest-path=b/Cargo.toml")
+    cargo
         .env("CARGO_TARGET_DIR", "target_moved")
         .with_stderr(
             "\
diff --git a/tests/testsuite/publish.rs b/tests/testsuite/publish.rs
index f0ebea8f788..82ca761d5c8 100644
--- a/tests/testsuite/publish.rs
+++ b/tests/testsuite/publish.rs
@@ -407,16 +407,16 @@ fn dont_publish_dirty() {
         .file(
             "Cargo.toml",
             r#"
-            [project]
-            name = "foo"
-            version = "0.0.1"
-            authors = []
-            license = "MIT"
-            description = "foo"
-            documentation = "foo"
-            homepage = "foo"
-            repository = "foo"
-        "#,
+                [project]
+                name = "foo"
+                version = "0.0.1"
+                authors = []
+                license = "MIT"
+                description = "foo"
+                documentation = "foo"
+                homepage = "foo"
+                repository = "foo"
+            "#,
         ).file("src/main.rs", "fn main() {}")
         .build();
 
diff --git a/tests/testsuite/registry.rs b/tests/testsuite/registry.rs
index c449198e528..e1bc4d00ec9 100644
--- a/tests/testsuite/registry.rs
+++ b/tests/testsuite/registry.rs
@@ -405,10 +405,9 @@ fn lockfile_locks() {
 ",
         ).run();
 
-    p.root().move_into_the_past();
     Package::new("bar", "0.0.2").publish();
 
-    p.cargo("build").with_stdout("").run();
+    p.cargo("build").with_stderr("[FINISHED] [..]\n").run();
 }
 
 #[test]
@@ -444,11 +443,10 @@ fn lockfile_locks_transitively() {
 ",
         ).run();
 
-    p.root().move_into_the_past();
     Package::new("baz", "0.0.2").publish();
     Package::new("bar", "0.0.2").dep("baz", "*").publish();
 
-    p.cargo("build").with_stdout("").run();
+    p.cargo("build").with_stderr("[FINISHED] [..]\n").run();
 }
 
 #[test]
@@ -548,7 +546,7 @@ fn yanks_in_lockfiles_are_ok() {
 
     Package::new("bar", "0.0.1").yanked(true).publish();
 
-    p.cargo("build").with_stdout("").run();
+    p.cargo("build").with_stderr("[FINISHED] [..]\n").run();
 
     p.cargo("update")
         .with_status(101)
@@ -580,7 +578,6 @@ fn update_with_lockfile_if_packages_missing() {
 
     Package::new("bar", "0.0.1").publish();
     p.cargo("build").run();
-    p.root().move_into_the_past();
 
     paths::home().join(".cargo/registry").rm_rf();
     p.cargo("build")
@@ -886,7 +883,6 @@ fn git_and_registry_dep() {
 
     Package::new("a", "0.0.1").publish();
 
-    p.root().move_into_the_past();
     p.cargo("build")
         .with_stderr(
             "\
@@ -898,11 +894,11 @@ fn git_and_registry_dep() {
 [COMPILING] foo v0.0.1 (CWD)
 [FINISHED] dev [unoptimized + debuginfo] target(s) in [..]s
 ",
-        ).run();
-    p.root().move_into_the_past();
+        )
+        .run();
 
     println!("second");
-    p.cargo("build").with_stdout("").run();
+    p.cargo("build").with_stderr("[FINISHED] [..]\n").run();
 }
 
 #[test]
diff --git a/tests/testsuite/rename_deps.rs b/tests/testsuite/rename_deps.rs
index 2716b3b9189..7e2e86e08da 100644
--- a/tests/testsuite/rename_deps.rs
+++ b/tests/testsuite/rename_deps.rs
@@ -259,7 +259,7 @@ name, but the dependency on `foo v0.1.0` is listed as having different names
 fn rename_affects_fingerprint() {
     Package::new("foo", "0.1.0").publish();
 
-    let p = project()
+    let mut p = project()
         .file(
             "Cargo.toml",
             r#"
@@ -278,7 +278,7 @@ fn rename_affects_fingerprint() {
 
     p.cargo("build -v").masquerade_as_nightly_cargo().run();
 
-    p.change_file(
+    p.write_file(
         "Cargo.toml",
         r#"
                 cargo-features = ["rename-dependency"]
diff --git a/tests/testsuite/rustc_info_cache.rs b/tests/testsuite/rustc_info_cache.rs
index defd26dae48..29902db6e98 100644
--- a/tests/testsuite/rustc_info_cache.rs
+++ b/tests/testsuite/rustc_info_cache.rs
@@ -1,5 +1,5 @@
 use std::env;
-use support::paths::CargoPathExt;
+use filetime::{self, FileTime};
 use support::{basic_manifest, project};
 
 #[test]
@@ -79,7 +79,9 @@ fn rustc_info_cache() {
         .with_stderr_does_not_contain(update)
         .run();
 
-    other_rustc.move_into_the_future();
+    let mtime = FileTime::from_last_modification_time(&other_rustc.metadata().unwrap());
+    let mtime = FileTime::from_unix_time(mtime.unix_seconds() + 1, mtime.nanoseconds());
+    filetime::set_file_times(&other_rustc, mtime, mtime).unwrap();
 
     p.cargo("build")
         .env("RUST_LOG", "cargo::util::rustc=info")
diff --git a/tests/testsuite/support/mod.rs b/tests/testsuite/support/mod.rs
index e898a96d3f6..7bd8e45e202 100644
--- a/tests/testsuite/support/mod.rs
+++ b/tests/testsuite/support/mod.rs
@@ -104,20 +104,22 @@ dependency.
 
 */
 
+use std::collections::HashMap;
 use std::env;
 use std::ffi::OsStr;
 use std::fmt;
-use std::fs;
+use std::fs::{self, File};
 use std::io::prelude::*;
 use std::os;
 use std::path::{Path, PathBuf};
 use std::process::{Command, Output};
 use std::str;
-use std::time::Duration;
+use std::thread;
 use std::usize;
 
-use cargo;
 use cargo::util::{CargoResult, ProcessBuilder, ProcessError, Rustc};
+use cargo;
+use filetime::{self, FileTime};
 use serde_json::{self, Value};
 use url::Url;
 
@@ -201,7 +203,21 @@ impl SymlinkBuilder {
 }
 
 pub struct Project {
+    /// Absolute path to the directory containing `Cargo.toml` for this project.
     root: PathBuf,
+    /// `mtime` of a file at the very start of the build, which is used to
+    /// ensure that all files are always set to this `mtime`. This is set on
+    /// `build`.
+    start: FileTime,
+    /// A map of files which have been updated since this project was created,
+    /// and the `FileTime` entry is the mtime to set the file to.
+    updates: HashMap<PathBuf, FileTime>,
+    /// Each time a file is created/updated we'll simulate time passing, and
+    /// this counter keeps track of how many times that's happened.
+    next_update: i64,
+    /// An escape hatch for a few existing tests to opt out of dealing with
+    /// `touch_everything_to_start`, shouldn't be used for new tests!
+    disable_mtime_management: bool,
 }
 
 #[must_use]
@@ -225,7 +241,7 @@ impl ProjectBuilder {
 
     pub fn new(root: PathBuf) -> ProjectBuilder {
         ProjectBuilder {
-            root: Project { root },
+            root: Project::at(root),
             files: vec![],
             symlinks: vec![],
             no_manifest: false,
@@ -233,9 +249,7 @@ impl ProjectBuilder {
     }
 
     pub fn at<P: AsRef<Path>>(mut self, path: P) -> Self {
-        self.root = Project {
-            root: paths::root().join(path),
-        };
+        self.root = Project::at(paths::root().join(path));
         self
     }
 
@@ -285,8 +299,11 @@ impl ProjectBuilder {
             symlink.mk();
         }
 
-        let ProjectBuilder { root, .. } = self;
-        root
+        let start = paths::home().join(".start");
+        File::create(&start).unwrap();
+        let ProjectBuilder { mut root, .. } = self;
+        root.start = FileTime::from_last_modification_time(&start.metadata().unwrap());
+        return root
     }
 
     fn rm_root(&self) {
@@ -295,11 +312,41 @@ impl ProjectBuilder {
 }
 
 impl Project {
+    fn at(root: PathBuf) -> Project {
+        Project {
+            root,
+            start: FileTime::zero(),
+            next_update: 1,
+            updates: HashMap::new(),
+            disable_mtime_management: false,
+        }
+    }
+
     /// Root of the project, ex: `/path/to/cargo/target/cit/t0/foo`
     pub fn root(&self) -> PathBuf {
         self.root.clone()
     }
 
+    pub fn set_root(&mut self, root: &Path) {
+        self.root = root.to_path_buf();
+    }
+
+    pub fn disable_mtime_management(&mut self) {
+        self.disable_mtime_management = true;
+    }
+
+    pub fn write_file(&mut self, path: &str, contents: &str) {
+        let path = self.root().join(path);
+        fs::write(&path, contents).unwrap();
+        let seconds_offset = self.next_update;
+        self.next_update += 1;
+        let new_time = FileTime::from_unix_time(
+            self.start.unix_seconds() + seconds_offset * 100,
+            self.start.nanoseconds(),
+        );
+        self.updates.insert(path, new_time);
+    }
+
     /// Project's target dir, ex: `/path/to/cargo/target/cit/t0/foo/target`
     pub fn build_dir(&self) -> PathBuf {
         self.root().join("target")
@@ -356,11 +403,6 @@ impl Project {
         ))
     }
 
-    /// Change the contents of an existing file.
-    pub fn change_file(&self, path: &str, body: &str) {
-        FileBuilder::new(self.root().join(path), body).mk()
-    }
-
     /// Create a `ProcessBuilder` to run a program in the project
     /// and wrap it in an Execs to assert on the execution.
     /// Example:
@@ -382,6 +424,7 @@ impl Project {
         if let Some(ref mut p) = execs.process_builder {
             split_and_add_args(p, cmd);
         }
+        self.touch_everything_to_start(&self.root);
         execs
     }
 
@@ -449,6 +492,36 @@ impl Project {
             _ => unreachable!(),
         }
     }
+
+    pub fn move_start_back_one_second(&mut self) {
+        self.start = FileTime::from_unix_time(
+            self.start.unix_seconds() - 1,
+            self.start.nanoseconds(),
+        );
+    }
+
+    fn touch_everything_to_start(&self, dir: &Path) {
+        if self.disable_mtime_management {
+            return
+        }
+        // ignore the target directory as it's got Cargo-specific files in there
+        if dir.file_name().unwrap() == "target" {
+            return
+        }
+        for entry in dir.read_dir().unwrap() {
+            let entry = entry.unwrap();
+            let path = entry.path();
+            let file_type = entry.file_type().unwrap();
+            if file_type.is_dir() {
+                self.touch_everything_to_start(&path);
+            } else if file_type.is_file() {
+                let new_time = self.updates.get(&path).cloned().unwrap_or(self.start);
+                paths::do_op(&path, "set file times", |path| {
+                    filetime::set_file_times(path, new_time, new_time)
+                });
+            }
+        }
+    }
 }
 
 // Generates a project layout
@@ -1131,7 +1204,7 @@ impl Execs {
 
 impl Drop for Execs {
     fn drop(&mut self) {
-        if !self.ran {
+        if !self.ran && !thread::panicking() {
             panic!("forgot to run this command");
         }
     }
@@ -1485,7 +1558,3 @@ pub fn git_process(s: &str) -> ProcessBuilder {
     split_and_add_args(&mut p, s);
     p
 }
-
-pub fn sleep_ms(ms: u64) {
-    ::std::thread::sleep(Duration::from_millis(ms));
-}
diff --git a/tests/testsuite/support/paths.rs b/tests/testsuite/support/paths.rs
index a5544ba0b77..4878d742363 100644
--- a/tests/testsuite/support/paths.rs
+++ b/tests/testsuite/support/paths.rs
@@ -6,8 +6,6 @@ use std::path::{Path, PathBuf};
 use std::sync::atomic::{AtomicUsize, Ordering, ATOMIC_USIZE_INIT};
 use std::sync::{Once, ONCE_INIT};
 
-use filetime::{self, FileTime};
-
 static CARGO_INTEGRATION_TEST_DIR: &'static str = "cit";
 static NEXT_ID: AtomicUsize = ATOMIC_USIZE_INIT;
 
@@ -58,18 +56,6 @@ pub fn home() -> PathBuf {
 pub trait CargoPathExt {
     fn rm_rf(&self);
     fn mkdir_p(&self);
-
-    fn move_into_the_past(&self) {
-        self.move_in_time(|sec, nsec| (sec - 3600, nsec))
-    }
-
-    fn move_into_the_future(&self) {
-        self.move_in_time(|sec, nsec| (sec + 3600, nsec))
-    }
-
-    fn move_in_time<F>(&self, travel_amount: F)
-    where
-        F: Fn(i64, u32) -> (i64, u32);
 }
 
 impl CargoPathExt for Path {
@@ -99,52 +85,9 @@ impl CargoPathExt for Path {
         fs::create_dir_all(self)
             .unwrap_or_else(|e| panic!("failed to mkdir_p {}: {}", self.display(), e))
     }
-
-    fn move_in_time<F>(&self, travel_amount: F)
-    where
-        F: Fn(i64, u32) -> ((i64, u32)),
-    {
-        if self.is_file() {
-            time_travel(self, &travel_amount);
-        } else {
-            recurse(self, &self.join("target"), &travel_amount);
-        }
-
-        fn recurse<F>(p: &Path, bad: &Path, travel_amount: &F)
-        where
-            F: Fn(i64, u32) -> ((i64, u32)),
-        {
-            if p.is_file() {
-                time_travel(p, travel_amount)
-            } else if !p.starts_with(bad) {
-                for f in t!(fs::read_dir(p)) {
-                    let f = t!(f).path();
-                    recurse(&f, bad, travel_amount);
-                }
-            }
-        }
-
-        fn time_travel<F>(path: &Path, travel_amount: &F)
-        where
-            F: Fn(i64, u32) -> ((i64, u32)),
-        {
-            let stat = t!(path.metadata());
-
-            let mtime = FileTime::from_last_modification_time(&stat);
-
-            let (sec, nsec) = travel_amount(mtime.unix_seconds(), mtime.nanoseconds());
-            let newtime = FileTime::from_unix_time(sec, nsec);
-
-            // Sadly change_file_times has a failure mode where a readonly file
-            // cannot have its times changed on windows.
-            do_op(path, "set file times", |path| {
-                filetime::set_file_times(path, newtime, newtime)
-            });
-        }
-    }
 }
 
-fn do_op<F>(path: &Path, desc: &str, mut f: F)
+pub fn do_op<F>(path: &Path, desc: &str, mut f: F)
 where
     F: FnMut(&Path) -> io::Result<()>,
 {
diff --git a/tests/testsuite/test.rs b/tests/testsuite/test.rs
index 5a2fdf730b7..1da33df7126 100644
--- a/tests/testsuite/test.rs
+++ b/tests/testsuite/test.rs
@@ -1,11 +1,7 @@
-use std::fs::File;
-use std::io::prelude::*;
-
 use cargo;
-use support::paths::CargoPathExt;
 use support::registry::Package;
 use support::{basic_bin_manifest, basic_lib_manifest, basic_manifest, cargo_exe, project};
-use support::{is_nightly, rustc_host, sleep_ms};
+use support::{is_nightly, rustc_host};
 
 #[test]
 fn cargo_test_simple() {
@@ -1042,7 +1038,6 @@ fn test_dylib() {
         ).with_stdout_contains_n("test foo ... ok", 2)
         .run();
 
-    p.root().move_into_the_past();
     p.cargo("test")
         .with_stderr(
             "\
@@ -1558,7 +1553,6 @@ fn build_then_selective_test() {
         .build();
 
     p.cargo("build").run();
-    p.root().move_into_the_past();
     p.cargo("test -p b").run();
 }
 
@@ -2151,15 +2145,11 @@ fn bin_does_not_rebuild_tests() {
         .file("src/lib.rs", "")
         .file("src/main.rs", "fn main() {}")
         .file("tests/foo.rs", "");
-    let p = p.build();
+    let mut p = p.build();
 
     p.cargo("test -v").run();
 
-    sleep_ms(1000);
-    File::create(&p.root().join("src/main.rs"))
-        .unwrap()
-        .write_all(b"fn main() { 3; }")
-        .unwrap();
+    p.write_file("src/main.rs", "fn main() { 3; }");
 
     p.cargo("test -v --no-run")
         .with_stderr(
diff --git a/tests/testsuite/workspaces.rs b/tests/testsuite/workspaces.rs
index 17c28009ffd..b579aa12754 100644
--- a/tests/testsuite/workspaces.rs
+++ b/tests/testsuite/workspaces.rs
@@ -1,9 +1,8 @@
 use std::env;
 use std::fs::{self, File};
-use std::io::{Read, Write};
+use std::io::Read;
 
 use support::registry::Package;
-use support::sleep_ms;
 use support::{basic_lib_manifest, basic_manifest, git, project};
 
 #[test]
@@ -1004,14 +1003,11 @@ fn rebuild_please() {
             }
         "#,
         );
-    let p = p.build();
+    let mut p = p.build();
 
     p.cargo("run").cwd(p.root().join("bin")).run();
 
-    sleep_ms(1000);
-
-    t!(t!(File::create(p.root().join("lib/src/lib.rs")))
-        .write_all(br#"pub fn foo() -> u32 { 1 }"#));
+    p.write_file("lib/src/lib.rs", "pub fn foo() -> u32 { 1 }");
 
     p.cargo("build").cwd(p.root().join("lib")).run();