refactor(coverage): simplify trap and improve hook coverage tests

- Simplify DEBUG trap to avoid redundant should_track calls
- Remove duplicate default path logic from coverage::init
- Fix escaped quotes in fixture file
- Add end-to-end test for coverage hooks via external bashunit run

Author: Chemaclass

src/coverage.sh

@@ -82,12 +82,6 @@ function bashunit::coverage::init() {
   export _BASHUNIT_COVERAGE_TRACKED_FILES
   export _BASHUNIT_COVERAGE_TRACKED_CACHE_FILE
   export _BASHUNIT_COVERAGE_TEST_HITS_FILE
-
-  # Ensure we have inclusion paths; if none provided or auto-discovered,
-  # default to tracking the src/ folder to avoid empty reports
-  if [[ -z "${BASHUNIT_COVERAGE_PATHS:-}" ]]; then
-    BASHUNIT_COVERAGE_PATHS="src/"
-  fi
 }
 
 function bashunit::coverage::enable_trap() {
@@ -101,18 +95,7 @@ function bashunit::coverage::enable_trap() {
   # Set DEBUG trap to record line execution
   # Use ${VAR:-} to handle unset variables when set -u is active (in subshells)
   # shellcheck disable=SC2154
-  trap '
-    # Prefer immediate callee frame; fall back to caller when current file is excluded
-    local __cov_file="${BASH_SOURCE[0]:-}"
-    local __cov_line="${LINENO:-}"
-    if [[ -n "$__cov_file" ]] && ! bashunit::coverage::should_track "$__cov_file"; then
-      # Try next stack frame if available (e.g., called function from a tracked src file)
-      if [[ -n "${BASH_SOURCE[1]:-}" ]]; then
-        __cov_file="${BASH_SOURCE[1]}"
-      fi
-    fi
-    bashunit::coverage::record_line "$__cov_file" "$__cov_line"
-  ' DEBUG
+  trap 'bashunit::coverage::record_line "${BASH_SOURCE[0]:-}" "${LINENO:-}"' DEBUG
 }
 
 function bashunit::coverage::disable_trap() {

tests/acceptance/coverage_hooks_test.sh

@@ -1,14 +1,16 @@
 #!/usr/bin/env bash
+# shellcheck disable=SC2034
 
 function set_up_before_script() {
     TEST_ENV_FILE="tests/acceptance/fixtures/.env.default"
     LCOV_FILE="$(bashunit::temp_file "lcov-output")"
+    LCOV_FILE_EXTERNAL="$(bashunit::temp_file "lcov-external")"
 }
 
 function test_coverage_includes_src_hits_from_setup_hook() {
     # Enable coverage in-process and exercise code in a hook-like context
     BASHUNIT_COVERAGE=true
-    BASHUNIT_COVERAGE_PATHS="" # force auto-discovery / fallback
+    BASHUNIT_COVERAGE_PATHS="src/"
     bashunit::coverage::init
 
     # Simulate hook execution with coverage trap enabled
@@ -26,3 +28,21 @@ function test_coverage_includes_src_hits_from_setup_hook() {
     assert_contains "SF:$(pwd)/src/" "$lcov"
     assert_contains "DA:" "$lcov"
 }
+
+function test_coverage_hooks_via_external_bashunit() {
+    # Run bashunit on fixture with coverage enabled and verify hook code is tracked
+    local output
+    output=$(BASHUNIT_COVERAGE=true \
+             BASHUNIT_COVERAGE_PATHS="src/" \
+             BASHUNIT_COVERAGE_REPORT="$LCOV_FILE_EXTERNAL" \
+             ./bashunit tests/acceptance/fixtures/test_coverage_hooks.sh --simple 2>&1)
+
+    assert_successful_code
+
+    # Verify LCOV file was created with coverage data
+    assert_file_exists "$LCOV_FILE_EXTERNAL"
+    local lcov
+    lcov="$(cat "$LCOV_FILE_EXTERNAL" 2>/dev/null)"
+    assert_contains "SF:" "$lcov"
+    assert_contains "DA:" "$lcov"
+}

tests/acceptance/fixtures/test_coverage_hooks.sh

@@ -5,7 +5,7 @@
 function set_up() {
     # Invoke src functions to generate attributable coverage hits
     local f
-    f="$(bashunit::temp_file \"cov-hooks\")"
+    f="$(bashunit::temp_file "cov-hooks")"
     [[ -n "${f:-}" ]] && echo "tmp created" > /dev/null
 }