Merge pull request #427 from TypedDevs/refactor/improve-clock-performance-2

Improve clock performance

Author: Chemaclass

CHANGELOG.md

@@ -9,6 +9,7 @@
 - Add benchmark feature
 - Support placeholder `::ignore::` in snapshots
 - Add project overview docs
+- Improve clock performance
 
 ## [0.20.0](https://github.com/TypedDevs/bashunit/compare/0.19.1...0.20.0) - 2025-06-01
 

src/clock.sh

@@ -1,67 +1,67 @@
 #!/usr/bin/env bash
 
 function clock::now() {
-  if dependencies::has_perl && perl -MTime::HiRes -e "" > /dev/null 2>&1; then
-    if perl -MTime::HiRes -e 'printf("%.0f\n",Time::HiRes::time()*1000000000)'; then
-        return 0
-    fi
+  local shell_time
+
+  # 1. Try using native shell EPOCHREALTIME (if available)
+  if shell_time="$(clock::shell_time)"; then
+    local seconds="${shell_time%%.*}"
+    local microseconds="${shell_time#*.}"
+    math::calculate "($seconds * 1000000000) + ($microseconds * 1000)"
+    return 0
   fi
 
+  # 2. Try Perl with Time::HiRes
+  if dependencies::has_perl && perl -MTime::HiRes -e "" &>/dev/null; then
+    perl -MTime::HiRes -e 'printf("%.0f\n", Time::HiRes::time() * 1000000000)' && return 0
+  fi
+
+  # 3. Windows fallback with PowerShell
   if check_os::is_windows && dependencies::has_powershell; then
-      powershell -Command "
-              \$unixEpoch = [DateTime]'1970-01-01 00:00:00';
-              \$now = [DateTime]::UtcNow;
-              \$ticksSinceEpoch = (\$now - \$unixEpoch).Ticks;
-              \$nanosecondsSinceEpoch = \$ticksSinceEpoch * 100;
-              Write-Output \$nanosecondsSinceEpoch
-              "
-      return 0
+    powershell -Command "
+      \$unixEpoch = [DateTime]'1970-01-01 00:00:00';
+      \$now = [DateTime]::UtcNow;
+      \$ticksSinceEpoch = (\$now - \$unixEpoch).Ticks;
+      \$nanosecondsSinceEpoch = \$ticksSinceEpoch * 100;
+      Write-Output \$nanosecondsSinceEpoch
+    " && return 0
   fi
 
+  # 4. Unix fallback using `date +%s%N` (if not macOS or Alpine)
   if ! check_os::is_macos && ! check_os::is_alpine; then
     local result
-    result=$(date +%s%N)
-    if [[ "$result" != *N ]] && [[ "$result" -gt 0 ]]; then
+    result=$(date +%s%N 2>/dev/null)
+    if [[ "$result" != *N && "$result" =~ ^[0-9]+$ ]]; then
       echo "$result"
       return 0
     fi
   fi
 
-  local shell_time has_shell_time
-  shell_time="$(clock::shell_time)"
-  has_shell_time="$?"
-  if [[ "$has_shell_time" -eq 0 ]]; then
-    local  seconds microseconds
-    seconds=$(echo "$shell_time" | cut -f 1 -d '.')
-    microseconds=$(echo "$shell_time" | cut -f 2 -d '.')
-
-    math::calculate "($seconds * 1000000000) + ($microseconds * 1000)"
-    return 0
-  fi
-
+  # 5. All methods failed
   echo ""
   return 1
 }
 
 function clock::shell_time() {
-  # Get time directly from the shell rather than a program.
+  # Get time directly from the shell variable EPOCHREALTIME (Bash 5+)
   [[ -n ${EPOCHREALTIME+x} && -n "$EPOCHREALTIME" ]] && LC_ALL=C echo "$EPOCHREALTIME"
 }
 
-
 function clock::total_runtime_in_milliseconds() {
+  local end_time
   end_time=$(clock::now)
   if [[ -n $end_time ]]; then
-    math::calculate "($end_time-$_START_TIME)/1000000"
+    math::calculate "($end_time - $_START_TIME) / 1000000"
   else
     echo ""
   fi
 }
 
 function clock::total_runtime_in_nanoseconds() {
+  local end_time
   end_time=$(clock::now)
   if [[ -n $end_time ]]; then
-    math::calculate "($end_time-$_START_TIME)"
+    math::calculate "$end_time - $_START_TIME"
   else
     echo ""
   fi

tests/unit/clock_test.sh

@@ -15,13 +15,15 @@ function mock_non_existing_fn() {
 }
 
 function test_now_with_perl() {
+  mock clock::shell_time mock_non_existing_fn
   mock perl echo "1720705883457"
 
   assert_same "1720705883457" "$(clock::now)"
 }
 
 function test_now_on_linux_unknown() {
   mock_unknown_linux_os
+  mock clock::shell_time mock_non_existing_fn
   mock perl mock_non_existing_fn
   mock date echo "1720705883457"
 
@@ -30,6 +32,7 @@ function test_now_on_linux_unknown() {
 
 function test_now_on_linux_alpine() {
   mock_alpine_os
+  mock clock::shell_time mock_non_existing_fn
   mock perl echo "1720705883457"
 
   assert_same "1720705883457" "$(clock::now)"
@@ -40,6 +43,7 @@ function test_now_on_windows_without_with_powershell() {
   mock dependencies::has_perl mock_false
   mock dependencies::has_powershell mock_true
   mock powershell echo "1727768183281580800"
+  mock clock::shell_time mock_non_existing_fn
 
   assert_same "1727768183281580800" "$(clock::now)"
 }
@@ -49,6 +53,7 @@ function test_now_on_windows_without_without_powershell() {
   mock dependencies::has_perl mock_false
   mock dependencies::has_powershell mock_false
   mock date echo "1727768951"
+  mock clock::shell_time mock_non_existing_fn
 
   assert_same "1727768951" "$(clock::now)"
 }