add test_proc_macro library and use it in the test

Author: fedochet

Cargo.toml

@@ -9,4 +9,5 @@ proc-macro2 = "0.4.29"
 dylib = "0.0.3"
 goblin = "0.0.22"
 syn = "0.15.33"
-tempfile = "3"
+tempfile = "3"
+test_proc_macro = { path = "./test_proc_macro"}

src/main.rs

@@ -123,11 +123,29 @@ fn compile_proc_macro(dir: &PathBuf) -> io::Result<PathBuf> {
     }
 }
 
+fn find_test_proc_macro() -> io::Result<PathBuf> {
+    let mut test_exe = std::env::current_exe()?;
+    test_exe.pop();
+
+    for entry in fs::read_dir(&test_exe)? {
+        let entry = entry?;
+        let name = entry.file_name().to_str().unwrap().to_string();
+        if entry.path().is_file()
+            && name.starts_with("libtest_proc_macro")
+            && name.ends_with(".so") {
+            return Ok(entry.path());
+        }
+    }
+
+    Err(io::Error::from(ErrorKind::NotFound))
+}
+
 #[test]
 fn test_getset_expansion() -> io::Result<()> {
-    let tmp_dir = TempDir::new()?;
-    setup_temp_proc_macro_project(&tmp_dir.path().to_path_buf())?;
-    let proc_macro_lib = canonicalize(compile_proc_macro(&tmp_dir.path().to_path_buf())?)?;
+//    let tmp_dir = TempDir::new()?;
+//    setup_temp_proc_macro_project(&tmp_dir.path().to_path_buf())?;
+//    let proc_macro_lib = canonicalize(compile_proc_macro(&tmp_dir.path().to_path_buf())?)?;
+    let proc_macro_lib = find_test_proc_macro()?;
 
     let symbol_name = find_registrar_symbol(&proc_macro_lib).expect(
         &format!("Cannot find registrar symbol in file {:?}", &proc_macro_lib)

test_proc_macro/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "test_proc_macro"
+version = "0.1.0"
+
+[lib]
+proc-macro = true
+
+[dependencies]

test_proc_macro/src/lib.rs

@@ -0,0 +1,8 @@
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+
+#[proc_macro]
+pub fn make_answer_macro(input: TokenStream) -> TokenStream {
+    "fn answer() -> u32 { 42 }".parse().unwrap()
+}