fix: make array iteration safe for strict mode (set -u)

When bashunit runs with BASHUNIT_STRICT_MODE=true (set -u), iterating
over arrays could trigger "unbound variable" errors. This fix implements
safe array iteration patterns:

- For value iteration: Use "${array[@]+"${array[@]}"}" pattern which
  expands to nothing when array is empty, preventing unbound errors
- For indexed iteration: Check array size before loop with
  [ "${#array[@]}" -gt 0 ] to avoid iterating over empty arrays
- Add default values (:-) when accessing array elements to handle
  unset elements gracefully

Changes affect:
- src/benchmark.sh: Safe iteration over benchmark result arrays
- src/env.sh: Safe iteration over environment variable keys
- src/helpers.sh: Safe iteration over function names
- src/main.sh: Safe iteration over command-line arguments
- src/parallel.sh: Safe iteration over result files
- src/reports.sh: Safe iteration over test results
- src/runner.sh: Safe iteration over test files and functions
- src/test_doubles.sh: Safe iteration over mocked functions

All tests passing locally (738 passed, 3 skipped, 7 incomplete).
Fixes strict mode compatibility without breaking existing functionality.

Author: Chemaclass

src/benchmark.sh

@@ -87,7 +87,7 @@ function bashunit::benchmark::run_function() {
 
   local sum=0
   local d
-  for d in "${durations[@]}"; do
+  for d in "${durations[@]+"${durations[@]}"}"; do
     sum=$(bashunit::math::calculate "$sum + $d")
   done
   local avg=$(bashunit::math::calculate "$sum / ${#durations[@]}")
@@ -113,7 +113,7 @@ function bashunit::benchmark::print_results() {
 
   local has_threshold=false
   local val
-  for val in "${_BASHUNIT_BENCH_MAX_MILLIS[@]}"; do
+  for val in "${_BASHUNIT_BENCH_MAX_MILLIS[@]+"${_BASHUNIT_BENCH_MAX_MILLIS[@]}"}"; do
     if [[ -n "$val" ]]; then
       has_threshold=true
       break
@@ -126,13 +126,17 @@ function bashunit::benchmark::print_results() {
     printf '%-40s %6s %6s %10s\n' "Name" "Revs" "Its" "Avg(ms)"
   fi
 
-  local i=0
+  if [ "${#_BASHUNIT_BENCH_NAMES[@]}" -eq 0 ]; then
+    return
+  fi
+
+  local i
   for i in "${!_BASHUNIT_BENCH_NAMES[@]}"; do
-    local name="${_BASHUNIT_BENCH_NAMES[$i]}"
-    local revs="${_BASHUNIT_BENCH_REVS[$i]}"
-    local its="${_BASHUNIT_BENCH_ITS[$i]}"
-    local avg="${_BASHUNIT_BENCH_AVERAGES[$i]}"
-    local max_ms="${_BASHUNIT_BENCH_MAX_MILLIS[$i]}"
+    local name="${_BASHUNIT_BENCH_NAMES[$i]:-}"
+    local revs="${_BASHUNIT_BENCH_REVS[$i]:-}"
+    local its="${_BASHUNIT_BENCH_ITS[$i]:-}"
+    local avg="${_BASHUNIT_BENCH_AVERAGES[$i]:-}"
+    local max_ms="${_BASHUNIT_BENCH_MAX_MILLIS[$i]:-}"
 
     if [[ -z "$max_ms" ]]; then
       printf '%-40s %6s %6s %10s\n' "$name" "$revs" "$its" "$avg"

src/env.sh

@@ -245,13 +245,13 @@ function bashunit::env::print_verbose() {
   local max_length=0
 
   local key=""
-  for key in "${keys[@]}"; do
+  for key in "${keys[@]+"${keys[@]}"}"; do
     if (( ${#key} > max_length )); then
       max_length=${#key}
     fi
   done
 
-  for key in "${keys[@]}"; do
+  for key in "${keys[@]+"${keys[@]}"}"; do
     bashunit::internal_log "$key=${!key}"
     printf "%s:%*s%s\n" "$key" $((max_length - ${#key} + 1)) "" "${!key}"
   done

src/helpers.sh

@@ -361,7 +361,7 @@ function bashunit::helper::find_total_tests() {
                 local -a provider_data=()
                 local provider_data_count=0
                 local fn_name line
-                for fn_name in "${functions_to_run[@]}"; do
+                for fn_name in "${functions_to_run[@]+"${functions_to_run[@]}"}"; do
                     provider_data=()
                     provider_data_count=0
                     while IFS=" " read -r line; do

src/main.sh

@@ -180,7 +180,7 @@ function bashunit::main::cmd_test() {
     else
       # Test mode: process file paths and extract inline filters
       local arg=""
-      for arg in "${raw_args[@]}"; do
+      for arg in "${raw_args[@]+"${raw_args[@]}"}"; do
         local parsed_path parsed_filter
         {
           read -r parsed_path
@@ -321,7 +321,7 @@ function bashunit::main::cmd_bench() {
   # Expand positional arguments
   if [[ "$raw_args_count" -gt 0 ]]; then
     local arg file
-    for arg in "${raw_args[@]}"; do
+    for arg in "${raw_args[@]+"${raw_args[@]}"}"; do
       while IFS= read -r file; do
         args[args_count]="$file"; args_count=$((args_count + 1))
       done < <(bashunit::helper::find_files_recursive "$arg" '*[bB]ench.sh')

src/parallel.sh

@@ -25,7 +25,7 @@ function bashunit::parallel::aggregate_test_results() {
     fi
 
     local result_file=""
-    for result_file in "${result_files[@]}"; do
+    for result_file in "${result_files[@]+"${result_files[@]}"}"; do
       local result_line
       result_line=$(tail -n 1 < "$result_file")
 

src/reports.sh

@@ -64,11 +64,11 @@ function bashunit::reports::generate_junit_xml() {
 
     local i=0
     for i in "${!_BASHUNIT_REPORTS_TEST_NAMES[@]}"; do
-      local file="${_BASHUNIT_REPORTS_TEST_FILES[$i]}"
-      local name="${_BASHUNIT_REPORTS_TEST_NAMES[$i]}"
-      local assertions="${_BASHUNIT_REPORTS_TEST_ASSERTIONS[$i]}"
-      local status="${_BASHUNIT_REPORTS_TEST_STATUSES[$i]}"
-      local test_time="${_BASHUNIT_REPORTS_TEST_DURATIONS[$i]}"
+      local file="${_BASHUNIT_REPORTS_TEST_FILES[$i]:-}"
+      local name="${_BASHUNIT_REPORTS_TEST_NAMES[$i]:-}"
+      local assertions="${_BASHUNIT_REPORTS_TEST_ASSERTIONS[$i]:-}"
+      local status="${_BASHUNIT_REPORTS_TEST_STATUSES[$i]:-}"
+      local test_time="${_BASHUNIT_REPORTS_TEST_DURATIONS[$i]:-}"
 
       echo "    <testcase file=\"$file\""
       echo "        name=\"$name\""
@@ -100,10 +100,10 @@ function bashunit::reports::generate_report_html() {
   : > "$temp_file"  # Clear temp file if it exists
   local i=0
   for i in "${!_BASHUNIT_REPORTS_TEST_NAMES[@]}"; do
-    local file="${_BASHUNIT_REPORTS_TEST_FILES[$i]}"
-    local name="${_BASHUNIT_REPORTS_TEST_NAMES[$i]}"
-    local status="${_BASHUNIT_REPORTS_TEST_STATUSES[$i]}"
-    local test_time="${_BASHUNIT_REPORTS_TEST_DURATIONS[$i]}"
+    local file="${_BASHUNIT_REPORTS_TEST_FILES[$i]:-}"
+    local name="${_BASHUNIT_REPORTS_TEST_NAMES[$i]:-}"
+    local status="${_BASHUNIT_REPORTS_TEST_STATUSES[$i]:-}"
+    local test_time="${_BASHUNIT_REPORTS_TEST_DURATIONS[$i]:-}"
     local test_case="$file|$name|$status|$test_time"
 
     echo "$test_case" >> "$temp_file"

src/runner.sh

@@ -30,7 +30,7 @@ function bashunit::runner::load_test_files() {
   fi
 
   local test_file=""
-  for test_file in "${files[@]}"; do
+  for test_file in "${files[@]+"${files[@]}"}"; do
     if [[ ! -f $test_file ]]; then
       continue
     fi
@@ -103,7 +103,7 @@ function bashunit::runner::load_test_files() {
     disown "$spinner_pid" && kill "$spinner_pid" &>/dev/null
     printf "\r  \r" # Clear the spinner output
     local script_id=""
-    for script_id in "${scripts_ids[@]}"; do
+    for script_id in "${scripts_ids[@]+"${scripts_ids[@]}"}"; do
       export BASHUNIT_CURRENT_SCRIPT_ID="${script_id}"
       bashunit::cleanup_script_temp_files
     done
@@ -232,7 +232,7 @@ function bashunit::runner::parse_data_provider_args() {
         unset 'args[$last_idx]'
       fi
       # Print args and return early
-      for arg in "${args[@]}"; do
+      for arg in "${args[@]+"${args[@]}"}"; do
         encoded_arg="$(bashunit::helper::encode_base64 "${arg}")"
         printf '%s\n' "$encoded_arg"
       done
@@ -338,7 +338,7 @@ function bashunit::runner::call_test_functions() {
   local -a parsed_data=()
   local parsed_data_count=0
 
-  for fn_name in "${functions_to_run[@]}"; do
+  for fn_name in "${functions_to_run[@]+"${functions_to_run[@]}"}"; do
     if bashunit::parallel::is_enabled && bashunit::parallel::must_stop_on_failure; then
       break
     fi
@@ -361,7 +361,7 @@ function bashunit::runner::call_test_functions() {
 
     # Execute the test function for each line of data
     local data=""
-    for data in "${provider_data[@]}"; do
+    for data in "${provider_data[@]+"${provider_data[@]}"}"; do
       parsed_data=()
       parsed_data_count=0
       local line=""
@@ -403,7 +403,7 @@ function bashunit::runner::call_bench_functions() {
   fi
 
   local fn_name=""
-  for fn_name in "${functions_to_run[@]}"; do
+  for fn_name in "${functions_to_run[@]+"${functions_to_run[@]}"}"; do
     read -r revs its max_ms <<< "$(bashunit::benchmark::parse_annotations "$fn_name" "$script")"
     bashunit::benchmark::run_function "$fn_name" "$revs" "$its" "$max_ms"
     unset -v fn_name
@@ -1067,9 +1067,13 @@ function bashunit::runner::record_test_hook_failure() {
 }
 
 function bashunit::runner::clear_mocks() {
-  local i=0
+  if [ "${#_BASHUNIT_MOCKED_FUNCTIONS[@]}" -eq 0 ]; then
+    return
+  fi
+
+  local i
   for i in "${!_BASHUNIT_MOCKED_FUNCTIONS[@]}"; do
-    bashunit::unmock "${_BASHUNIT_MOCKED_FUNCTIONS[$i]}"
+    bashunit::unmock "${_BASHUNIT_MOCKED_FUNCTIONS[$i]:-}"
   done
 }
 

src/test_doubles.sh

@@ -5,9 +5,13 @@ declare -a _BASHUNIT_MOCKED_FUNCTIONS=()
 function bashunit::unmock() {
   local command=$1
 
-  local i=0
+  if [ "${#_BASHUNIT_MOCKED_FUNCTIONS[@]}" -eq 0 ]; then
+    return
+  fi
+
+  local i
   for i in "${!_BASHUNIT_MOCKED_FUNCTIONS[@]}"; do
-    if [[ "${_BASHUNIT_MOCKED_FUNCTIONS[$i]}" == "$command" ]]; then
+    if [[ "${_BASHUNIT_MOCKED_FUNCTIONS[$i]:-}" == "$command" ]]; then
       unset "_BASHUNIT_MOCKED_FUNCTIONS[$i]"
       unset -f "$command"
       local variable