Stabilize rewatch integration tests

Signed-off-by: Christoph Knittel <ck@cca.io>

Author: cknitt

rewatch/AGENTS.md

@@ -217,5 +217,5 @@ When clippy suggests refactoring that could impact performance, consider the tra
 ## CI Gotchas
 
 - **`sleep` is fragile** — Prefer polling (e.g., `wait_for_file`) over fixed sleeps. CI runners are slower than local machines.
-- **`exit_watcher` is async** — It only signals the watcher to stop (removes the lock file), it doesn't wait for the process to exit. Avoid triggering config-change events before exiting, as the watcher may start a concurrent rebuild.
+- **Wait for watcher shutdown with `exit_watcher`** — It removes the lock file and waits for the recorded watcher process to exit. Check its return status before continuing when later mutations could race with the watcher.
 - **`sed -i` differs across platforms** — macOS requires `sed -i '' ...`, Linux does not. Use the `replace` / `normalize_paths` helpers from `rewatch/tests/utils.sh` instead of raw `sed`.

rewatch/tests/clean/01-clean-single-project.sh

@@ -42,7 +42,7 @@ other_project_compiled_files=$(find packages/new-namespace -type f -name '*.mjs'
 if [ "$other_project_compiled_files" -gt 0 ];
 then
   success "Didn't clean other project files"
-  git restore .
+  restore_tracked_files .
 else
   error "Expected files from new-namespace not to be cleaned"
   exit 1

rewatch/tests/clean/02-clean-dev-dependencies.sh

@@ -31,7 +31,7 @@ project_compiled_files=$(find packages/pure-dev -type f -name '*.mjs' | wc -l |
 if [ "$project_compiled_files" -eq 0 ];
 then
   success "pure-dev cleaned"
-  git restore .
+  restore_tracked_files .
 else
   error "Expected 0 .mjs files in pure-dev after clean, got $project_compiled_files"
   printf "%s\n" "$error_output"

rewatch/tests/clean/03-clean-node-modules.sh

@@ -31,7 +31,7 @@ compiler_assets=$(find node_modules/rescript-nodejs/lib/ocaml -type f -name '*.*
 if [ $compiler_assets -eq 0 ];
 then
   success "compiler assets from node_modules cleaned"
-  git restore .
+  restore_tracked_files .
 else
   error "Expected 0 files in node_modules/rescript-nodejs/lib/ocaml after clean, got $compiler_assets"
   printf "%s\n" "$error_output"

rewatch/tests/clean/04-clean-rebuild-no-compiler-update.sh

@@ -18,24 +18,25 @@ else
   exit 1
 fi
 
-# Rebuild with snapshot output
-snapshot_file=../tests/snapshots/clean-rebuild.txt
-rewatch build &> $snapshot_file
+# Rebuild with captured output. This test checks one lifecycle message; writing
+# into a tracked snapshot made the fixture dirty whenever work counts changed.
+output_file=$(mktemp "${TMPDIR:-/tmp}/rewatch-clean-rebuild.XXXXXX")
+trap 'rm -f "$output_file"' EXIT
+rewatch build &> "$output_file"
 build_status=$?
-normalize_paths $snapshot_file
 if [ $build_status -eq 0 ];
 then
   success "Repo Built"
 else
   error "Error Building Repo"
-  cat $snapshot_file >&2
+  cat "$output_file" >&2
   exit 1
 fi
 
 # Verify the undesired message is NOT present
-if grep -q "Cleaned previous build due to compiler update" $snapshot_file; then
+if grep -q "Cleaned previous build due to compiler update" "$output_file"; then
   error "Unexpected compiler-update clean message present in rebuild logs"
-  cat $snapshot_file >&2
+  cat "$output_file" >&2
   exit 1
 else
   success "No compiler-update clean message present after explicit clean"

rewatch/tests/compile/08-remove-file.sh

@@ -11,7 +11,7 @@ rewatch build &> /dev/null
 rm packages/dep02/src/Dep02.res
 rewatch build &> ../tests/snapshots/remove-file.txt
 normalize_paths ../tests/snapshots/remove-file.txt
-git checkout -- packages/dep02/src/Dep02.res
+restore_tracked_files packages/dep02/src/Dep02.res
 
 rewatch build &> /dev/null
 

rewatch/tests/compile/09-dependency-cycle.sh

@@ -11,7 +11,7 @@ rewatch build &> /dev/null
 echo 'Dep01.log()' >> packages/new-namespace/src/NS_alias.res
 rewatch build &> ../tests/snapshots/dependency-cycle.txt
 normalize_paths ../tests/snapshots/dependency-cycle.txt
-git checkout -- packages/new-namespace/src/NS_alias.res
+restore_tracked_files packages/new-namespace/src/NS_alias.res
 
 rewatch build &> /dev/null
 

rewatch/tests/compile/11-dev-dependency-non-dev-source.sh

@@ -13,7 +13,7 @@ rewatch build &> /dev/null
 echo 'open WebAPI' >> packages/with-dev-deps/src/FileToTest.res
 rewatch build &> ../tests/snapshots/dev-dependency-used-by-non-dev-source.txt
 normalize_paths ../tests/snapshots/dev-dependency-used-by-non-dev-source.txt
-git checkout -- packages/with-dev-deps/src/FileToTest.res
+restore_tracked_files packages/with-dev-deps/src/FileToTest.res
 
 rewatch build &> /dev/null
 

rewatch/tests/compile/13-no-infinite-loop-with-cycle.sh

@@ -7,7 +7,7 @@ bold "Test: It should not loop when clean building with a cycle"
 
 rewatch clean &> /dev/null
 echo 'Dep01.log()' >> packages/new-namespace/src/NS_alias.res
-git checkout -- packages/new-namespace/src/NS_alias.res
+restore_tracked_files packages/new-namespace/src/NS_alias.res
 rewatch build &> /dev/null
 
 success "No infinite loop detected"

rewatch/tests/compile/17-prod-flag.sh

@@ -17,7 +17,7 @@ then
   success "Build without --prod correctly failed with nonexistent dev-dependency"
 else
   error "Build without --prod should have failed with nonexistent dev-dependency"
-  git checkout -- rescript.json
+  restore_tracked_files rescript.json
   exit 1
 fi
 
@@ -27,12 +27,12 @@ then
   success "Build with --prod succeeded despite nonexistent dev-dependency"
 else
   error "Build with --prod should have succeeded by skipping dev-dependencies"
-  git checkout -- rescript.json
+  restore_tracked_files rescript.json
   exit 1
 fi
 
 rewatch clean &> /dev/null
-git checkout -- rescript.json
+restore_tracked_files rescript.json
 
 # Test 2: --prod should skip dev source files
 rewatch clean &> /dev/null