perf(state): cache base64 -w flag detection at source time

Detect base64 -w flag support once at load time instead of running
base64 --help | grep on every test subshell exit. Also use the cached
flag in encode_base64 to avoid redundant command -v and error fallback.

Author: Chemaclass

src/helpers.sh

@@ -120,8 +120,10 @@ function bashunit::helper::encode_base64() {
     return
   fi
 
-  if command -v base64 >/dev/null; then
-    printf '%s' "$value" | base64 -w 0 2>/dev/null || printf '%s' "$value" | base64 | tr -d '\n'
+  if [[ "$_BASHUNIT_BASE64_WRAP_FLAG" == true ]]; then
+    printf '%s' "$value" | base64 -w 0
+  elif command -v base64 >/dev/null; then
+    printf '%s' "$value" | base64 | tr -d '\n'
   else
     printf '%s' "$value" | openssl enc -base64 -A
   fi

src/state.sh

@@ -1,5 +1,12 @@
 #!/usr/bin/env bash
 
+# Cache base64 -w flag support (Alpine needs -w 0, macOS does not support -w)
+if base64 --help 2>&1 | grep -q -- "-w"; then
+  _BASHUNIT_BASE64_WRAP_FLAG=true
+else
+  _BASHUNIT_BASE64_WRAP_FLAG=false
+fi
+
 _BASHUNIT_TESTS_PASSED=0
 _BASHUNIT_TESTS_FAILED=0
 _BASHUNIT_TESTS_SKIPPED=0
@@ -218,7 +225,7 @@ function bashunit::state::export_subshell_context() {
 
   local encoded_test_hook_message
 
-  if base64 --help 2>&1 | grep -q -- "-w"; then
+  if [[ "$_BASHUNIT_BASE64_WRAP_FLAG" == true ]]; then
     # Alpine requires the -w 0 option to avoid wrapping
     encoded_test_output=$(echo -n "$_BASHUNIT_TEST_OUTPUT" | base64 -w 0)
     encoded_test_title=$(echo -n "$_BASHUNIT_TEST_TITLE" | base64 -w 0)