feat: exclude well-known global cache directories

Add fixed directory exclusions for common tool caches (~/.cache,
~/.gradle/caches, ~/.m2/repository, ~/.npm/_cacache, ~/.nuget/packages,
~/.kube/cache) that are always safe to exclude without sentinel files.

Inspired by stevegrunwell#69, props @pkuczynski.

Author: django23

CHANGELOG.md

@@ -8,6 +8,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
+* Exclude well-known global cache directories (`~/.cache`, `~/.gradle/caches`, `~/.m2/repository`, `~/.npm/_cacache`, `~/.nuget/packages`, `~/.kube/cache`, etc.) without requiring sentinel files (inspired by [stevegrunwell/asimov#69], props @pkuczynski)
 * Exclude Next.js build cache (`.next`)
 * Exclude Nuxt build cache (`.nuxt`)
 * Exclude Angular CLI cache (`.angular`)
@@ -117,3 +118,4 @@ Initial public release.
 [#55]: https://github.com/stevegrunwell/asimov/pull/55
 [#35]: https://github.com/stevegrunwell/asimov/pull/35
 [#56]: https://github.com/stevegrunwell/asimov/pull/56
+[stevegrunwell/asimov#69]: https://github.com/stevegrunwell/asimov/pull/69

README.md

@@ -48,6 +48,7 @@ Asimov recognizes dependency directories across **30+ patterns** in these ecosys
 | **R** | `renv` |
 | **DevOps / IaC** | `.terraform`, `.terragrunt-cache`, `.vagrant`, `.direnv`, `cdk.out` |
 | **Game dev** | `.godot` |
+| **Global caches** | `~/.cache`, `~/.gradle/caches`, `~/.m2/repository`, `~/.npm/_cacache`, `~/.nuget/packages`, `~/.kube/cache` |
 
 Each directory is only excluded when its corresponding config file (the "sentinel") exists — so `node_modules` is only excluded if `package.json` is present, `vendor` only if `composer.json`, `go.mod`, or `Gemfile` exists, etc.
 
@@ -93,7 +94,7 @@ brew uninstall asimov
 
 ## How it works
 
-Asimov is a thin wrapper around Apple's [`tmutil`](https://ss64.com/mac/tmutil.html). It builds a single `find` command from all known dependency patterns, walks your home directory (skipping `~/Library` and `~/.Trash`), and pipes matching paths through `tmutil addexclusion`. Directories already excluded are skipped automatically — safe to run as often as you like.
+Asimov is a thin wrapper around Apple's [`tmutil`](https://ss64.com/mac/tmutil.html). It builds a single `find` command from all known dependency patterns, walks your home directory (skipping `~/Library` and `~/.Trash`), and pipes matching paths through `tmutil addexclusion`. It also unconditionally excludes well-known global tool caches (like `~/.cache`, `~/.gradle/caches`, and `~/.npm/_cacache`) that can always be safely restored. Directories already excluded are skipped automatically — safe to run as often as you like.
 
 ### Inspecting exclusions
 

asimov

@@ -93,6 +93,22 @@ readonly ASIMOV_VENDOR_DIR_SENTINELS=(
     'renv renv.lock'                   # renv (R)
 )
 
+# A list of fixed directories to exclude from Time Machine backups.
+#
+# Unlike sentinel-based pairs above, these directories are always excluded
+# when they exist — they represent global tool caches and artifacts that
+# can be safely restored.
+readonly ASIMOV_FIXED_DIRS=(
+    ~/.cache                           # XDG cache directory
+    ~/.gradle/caches                   # Gradle download cache
+    ~/.gradle/wrapper                  # Gradle wrapper distributions
+    ~/.m2/repository                   # Maven local repository
+    ~/.npm/_cacache                    # npm content-addressable cache
+    ~/.nuget/packages                  # NuGet global packages
+    ~/.kube/cache                      # Kubernetes API cache
+    ~/.kube/http-cache                 # Kubernetes HTTP cache
+)
+
 # Exclude the given paths from Time Machine backups.
 # Reads the newline-separated list of paths from stdin.
 exclude_file() {
@@ -144,3 +160,11 @@ printf '\n\033[0;36mFinding dependency directories with corresponding definition
 find "${ASIMOV_ROOT}" \( "${find_parameters_skip[@]}" \) \( -false "${find_parameters_vendor[@]}" \) \
     | exclude_file \
     ;
+
+# Exclude fixed directories (global tool caches) when they exist.
+printf '\n\033[0;36mExcluding known cache directories…\033[0m\n'
+for dir in "${ASIMOV_FIXED_DIRS[@]}"; do
+    if [[ -d "$dir" ]]; then
+        echo "$dir"
+    fi
+done | exclude_file

tests/behavior.bats

@@ -127,3 +127,45 @@ load test_helper
   refute_excluded "${HOME}/Code/My-Project/node_modules/dep/node_modules"
   [[ "$(count_exclusions)" -eq 1 ]]
 }
+
+# =============================================================================
+# Fixed directories (global caches)
+# =============================================================================
+
+@test "excludes fixed directory when it exists" {
+  mkdir -p "${HOME}/.cache"
+  run_asimov
+  assert_excluded "${HOME}/.cache"
+}
+
+@test "does not fail when fixed directory does not exist" {
+  # Don't create any fixed dirs — asimov should still succeed
+  run_asimov
+  [[ "$status" -eq 0 ]]
+  [[ "$(count_exclusions)" -eq 0 ]]
+}
+
+@test "excludes multiple fixed directories when they exist" {
+  mkdir -p "${HOME}/.cache"
+  mkdir -p "${HOME}/.gradle/caches"
+  mkdir -p "${HOME}/.npm/_cacache"
+  run_asimov
+  assert_excluded "${HOME}/.cache"
+  assert_excluded "${HOME}/.gradle/caches"
+  assert_excluded "${HOME}/.npm/_cacache"
+  [[ "$(count_exclusions)" -eq 3 ]]
+}
+
+@test "does not re-exclude already excluded fixed directory" {
+  mkdir -p "${HOME}/.cache"
+  run_asimov
+  assert_excluded "${HOME}/.cache"
+  local first_count
+  first_count="$(count_exclusions)"
+  [[ "$first_count" -eq 1 ]]
+
+  run_asimov
+  local second_count
+  second_count="$(count_exclusions)"
+  [[ "$second_count" -eq 1 ]]
+}