Merge pull request #1651 from cachix/direnv-feats

direnv: create upgrade path for direnvrc and fix more bugs
cachix · Dec 30, 2024 · 1cd2afa · 1cd2afa
2 parents 36df08e + 042a95f
commit 1cd2afa
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Showing 15 changed files with 261 additions and 56 deletions.
diff --git a/.envrc b/.envrc
@@ -7,7 +7,7 @@ set -euo pipefail
 nix build --print-out-paths --accept-flake-config || echo "nix build failed, using previous build"
 PATH_add "result/bin"
 
-# External users should use `source_url` to load this file
+# External users should eval `devenv direnvrc` or use `source_url` to load this file
 source_env ./direnvrc
 
 use devenv
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/devenv/Cargo.toml b/devenv/Cargo.toml
@@ -43,3 +43,4 @@ tracing-subscriber.workspace = true
 which.workspace = true
 whoami.workspace = true
 xdg.workspace = true
+once_cell = "1.20.2"
diff --git a/devenv/init/.envrc b/devenv/init/.envrc
@@ -1,5 +1,5 @@
 export DIRENV_WARN_TIMEOUT=20s
 
-source_url "https://raw.githubusercontent.com/cachix/devenv/82c0147677e510b247d8b9165c54f73d32dfd899/direnvrc" "sha256-7u4iDd1nZpxL4tCzmPG0dQgC5V+/44Ba+tHkPob1v2k="
+eval "$(devenv direnvrc)"
 
 use devenv
diff --git a/devenv/src/cli.rs b/devenv/src/cli.rs
@@ -264,7 +264,7 @@ pub enum Commands {
     Repl {},
 
     #[command(
-        about = "Deletes previous shell generations. See http://devenv.sh/garbage-collection"
+        about = "Deletes previous shell generations. See https://devenv.sh/garbage-collection"
     )]
     Gc {},
 
@@ -274,8 +274,13 @@ pub enum Commands {
         attributes: Vec<String>,
     },
 
+    #[command(
+        about = "Print a direnvrc that adds devenv support to direnv. See https://devenv.sh/automatic-shell-activation."
+    )]
+    Direnvrc,
+
     #[command(about = "Print the version of devenv.")]
-    Version {},
+    Version,
 
     #[clap(hide = true)]
     Assemble,

diff --git a/devenv/src/devenv.rs b/devenv/src/devenv.rs
@@ -6,6 +6,7 @@ use include_dir::{include_dir, Dir};
 use miette::{bail, Result};
 use nix::sys::signal;
 use nix::unistd::Pid;
+use once_cell::sync::Lazy;
 use serde::Deserialize;
 use sha2::Digest;
 use std::collections::HashMap;
@@ -22,6 +23,20 @@ const FLAKE_TMPL: &str = include_str!("flake.tmpl.nix");
 const REQUIRED_FILES: [&str; 4] = ["devenv.nix", "devenv.yaml", ".envrc", ".gitignore"];
 const EXISTING_REQUIRED_FILES: [&str; 1] = [".gitignore"];
 const PROJECT_DIR: Dir = include_dir!("$CARGO_MANIFEST_DIR/init");
+pub static DIRENVRC: Lazy<String> = Lazy::new(|| {
+    include_str!("../../direnvrc").replace(
+        "DEVENV_DIRENVRC_ROLLING_UPGRADE=0",
+        "DEVENV_DIRENVRC_ROLLING_UPGRADE=1",
+    )
+});
+pub static DIRENVRC_VERSION: Lazy<u8> = Lazy::new(|| {
+    DIRENVRC
+        .lines()
+        .find(|line| line.contains("export DEVENV_DIRENVRC_VERSION"))
+        .map(|line| line.split('=').last().unwrap().trim())
+        .and_then(|version| version.parse().ok())
+        .unwrap_or(0)
+});
 // project vars
 const DEVENV_FLAKE: &str = ".devenv.flake.nix";
 
@@ -817,6 +832,7 @@ impl Devenv {
             devenv_tmpdir = \"{}\";
             devenv_runtime = \"{}\";
             devenv_istesting = {};
+            devenv_direnvrc_latest_version = {};
             ",
             crate_version!(),
             self.global_options.system,
@@ -829,7 +845,8 @@ impl Devenv {
                 .unwrap_or_else(|| "null".to_string()),
             self.devenv_tmp,
             self.devenv_runtime.display(),
-            is_testing
+            is_testing,
+            DIRENVRC_VERSION.to_string()
         );
         let flake = FLAKE_TMPL.replace("__DEVENV_VARS__", &vars);
         let flake_path = self.devenv_root.join(DEVENV_FLAKE);
@@ -852,7 +869,7 @@ impl Devenv {
         let span = tracing::info_span!("building_shell", devenv.user_message = "Building shell",);
         let env = self.nix.dev_env(json, &gc_root).instrument(span).await?;
 
-        std::fs::write(
+        fs::write(
             self.devenv_dotfile.join("input-paths.txt"),
             env.paths
                 .iter()

diff --git a/devenv/src/flake.tmpl.nix b/devenv/src/flake.tmpl.nix
@@ -79,6 +79,11 @@
                 container.isBuilding = pkgs.lib.mkForce true;
                 containers.${container_name}.isBuilding = true;
               })
+              ({ options, ... }: {
+                config.devenv = pkgs.lib.optionalAttrs (builtins.hasAttr "direnvrcLatestVersion" options.devenv) {
+                  direnvrcLatestVersion = devenv_direnvrc_latest_version;
+                };
+              })
             ] ++ (map importModule (devenv.imports or [ ])) ++ [
               ./devenv.nix
               (devenv.devenv or { })

diff --git a/devenv/src/lib.rs b/devenv/src/lib.rs
@@ -5,5 +5,5 @@ mod devenv;
 pub mod log;
 
 pub use cli::{default_system, GlobalOptions};
-pub use devenv::{Devenv, DevenvOptions};
+pub use devenv::{Devenv, DevenvOptions, DIRENVRC, DIRENVRC_VERSION};
 pub use devenv_tasks as tasks;
diff --git a/devenv/src/main.rs b/devenv/src/main.rs
@@ -20,8 +20,11 @@ async fn main() -> Result<()> {
     };
 
     let command = match cli.command {
-        None => return print_version(),
-        Some(Commands::Version { .. }) => return print_version(),
+        None | Some(Commands::Version) => return print_version(),
+        Some(Commands::Direnvrc) => {
+            print!("{}", devenv::DIRENVRC.to_string());
+            return Ok(());
+        }
         Some(cmd) => cmd,
     };
 
@@ -156,6 +159,7 @@ async fn main() -> Result<()> {
             config::write_json_schema();
             Ok(())
         }
-        Commands::Version {} => unreachable!(),
+        Commands::Direnvrc => unreachable!(),
+        Commands::Version => unreachable!(),
     }
 }
diff --git a/direnvrc b/direnvrc
@@ -28,6 +28,9 @@ _nix_direnv_preflight () {
   if [[ ! -d "$layout_dir" ]]; then
     mkdir -p "$layout_dir"
   fi
+
+  export DEVENV_DIRENVRC_VERSION=1
+  export DEVENV_DIRENVRC_ROLLING_UPGRADE=0
 }
 
 _nix_export_or_unset() {
@@ -42,6 +45,11 @@ _nix_export_or_unset() {
 _nix_import_env() {
   local profile_rc=$1
 
+  # Note which environments are active, but make sure we don't repeat them
+  if [[ ! "''${DIRENV_ACTIVE-}" =~ (^|:)"$PWD"(:|$) ]]; then
+    export DIRENV_ACTIVE="$PWD:''${DIRENV_ACTIVE-}"
+  fi
+
   local old_nix_build_top=${NIX_BUILD_TOP:-__UNSET__}
   local old_tmp=${TMP:-__UNSET__}
   local old_tmpdir=${TMPDIR:-__UNSET__}
@@ -50,7 +58,7 @@ _nix_import_env() {
   local old_xdg_data_dirs=${XDG_DATA_DIRS:-}
   eval "$(< "$profile_rc")"
   # `nix print-dev-env` will create a temporary directory and use it as TMPDIR
-  # We cannot rely on this directory being availble at all times,
+  # We cannot rely on this directory being available at all times,
   # as it may be garbage collected.
   # Instead - just remove it immediately.
   # Use recursive & force as it may not be empty.
@@ -78,7 +86,10 @@ _nix_import_env() {
 _nix_argsum_suffix() {
   local out checksum content
 
-  content=$(cat "$@" 2>/dev/null)
+  args=("$@")
+  sorted_args=$(printf "%s\n" "${args[@]}" | sort -u)
+
+  content=$(cat "${sorted_args[@]}" 2>/dev/null)
 
   if has sha1sum; then
     out=$(sha1sum <<< "$content")
@@ -94,44 +105,87 @@ _nix_argsum_suffix() {
 }
 
 nix_direnv_watch_file() {
+  log_error "nix_direnv_watch_file is deprecated. Use watch_file instead."
   watch_file "$@"
-  nix_watches+=("$@")
+}
+
+_nix_direnv_watches() {
+  local -n _watches=$1
+  if [[ -z ${DIRENV_WATCHES-} ]]; then
+    return
+  fi
+  while IFS= read -r line; do
+    local regex='"[Pp]ath": "(.+)"$'
+    if [[ $line =~ $regex ]]; then
+      local path="${BASH_REMATCH[1]}"
+      if [[ $path == "${XDG_DATA_HOME:-${HOME:-/var/empty}/.local/share}/direnv/allow/"* ]]; then
+        continue
+      fi
+      # expand new lines and other json escapes
+      # shellcheck disable=2059
+      path=$(printf "$path")
+      _watches+=("$path")
+    fi
+  done < <($direnv show_dump "${DIRENV_WATCHES}")
+}
+
+_devenv_watches() {
+  local path=$1
+  local -n _watches=$2
+  if [[ -f "$path" ]]; then
+    while IFS= read -r file; do
+      file=$(printf "$file")
+      _watches+=("$file")
+    done < "$path"
+  fi
+}
+
+_devenv_profile_rc() {
+  local -n _watches=$1
+  local layout_dir profile
+  layout_dir=$(direnv_layout_dir)
+  profile="${layout_dir}/devenv-profile$(_nix_argsum_suffix "${_watches[@]}")"
+  echo "${profile}.rc"
 }
 
 use_devenv() {
   _nix_direnv_preflight
 
   flake_expr="${1:-.}"
   flake_dir="${flake_expr%#*}"
+  env_deps_path="$flake_dir/.devenv/input-paths.txt"
 
-  local files_to_watch
-  files_to_watch=(".envrc" "$HOME/.direnvrc" "$HOME/.config/direnv/direnvrc")
+  local default_watches
+  default_watches=(".envrc" "$HOME/.direnvrc" "$HOME/.config/direnv/direnvrc")
 
   if [[ -d "$flake_dir" ]]; then
-    files_to_watch+=("$flake_dir/devenv.nix" "$flake_dir/devenv.lock" "$flake_dir/devenv.yaml" "$flake_dir/devenv.local.nix")
+    default_watches+=("$flake_dir/devenv.nix" "$flake_dir/devenv.lock" "$flake_dir/devenv.yaml" "$flake_dir/devenv.local.nix")
+
     if [[ -f "$flake_dir/devenv.yaml" ]]; then
       if ! devenv assemble; then
         log_error "$(devenv version) failed to parse devenv.yaml, make sure to use version 0.6 or newer and fix the errors above."
         exit 0
       fi
-
-      if [[ -f "$flake_dir/.devenv/input-paths.txt" ]]; then
-        for file in $(cat "$flake_dir/.devenv/input-paths.txt"); do
-            files_to_watch+=("$file")
-        done
-      fi
     fi
   fi
 
-  nix_direnv_watch_file "${files_to_watch[@]}"
+  # Watch the default files
+  watch_file "${default_watches[@]}"
 
-  local layout_dir profile_rc
-  layout_dir=$(direnv_layout_dir)
-  profile_rc="${layout_dir}/devenv-profile$(_nix_argsum_suffix "${files_to_watch[@]}").rc"
+  # Fetch and watch files that affect the env
+  local env_watches
+  _devenv_watches "$env_deps_path" env_watches
+  watch_file "${env_watches[@]}"
+
+  # Fetch all files that direnv is currently watching
+  local watches
+  _nix_direnv_watches watches
+
+  profile_rc=$(_devenv_profile_rc watches)
 
   local need_update=0
   local file=
-  for file in "${nix_watches[@]}"; do
+  for file in "${watches[@]}"; do
     if [[ "$file" -nt "$profile_rc" ]]; then
       need_update=1
       log_status "$file changed, reloading"
@@ -148,6 +202,16 @@ use_devenv() {
       exit 0
     fi
 
+    # Re-watch files that affect the env
+    local env_watches
+    _devenv_watches "$env_deps_path" env_watches
+    watch_file "${env_watches[@]}"
+
+    # Fetch the final watches and compute the new profile_rc
+    local watches
+    _nix_direnv_watches watches
+    profile_rc=$(_devenv_profile_rc watches)
+
     echo "$env" > "$profile_rc"
     log_status "updated devenv shell cache"
     _nix_import_env "$profile_rc"