fix(timer): round duration before splitting off minutes (#14246)

plugins/timer/tests/timer.test.zsh

@@ -0,0 +1,39 @@
+#!/usr/bin/env zsh
+
+# Run with: zsh -df plugins/timer/tests/timer.test.zsh
+emulate -L zsh
+
+source "${0:A:h:h}/timer.plugin.zsh"
+
+typeset -i failures=0 tests=0
+
+check_duration() {
+  local precision=$1 duration=$2 expected=$3
+  local output=$(TIMER_PRECISION=$precision __timer_format_duration $duration)
+  (( tests++ ))
+
+  if [[ $output == "$expected" ]]; then
+    print -r -- "PASS: $duration with precision $precision -> $output"
+  else
+    print -u2 -r -- "FAIL: $duration with precision $precision -> $output (expected $expected)"
+    (( failures++ ))
+  fi
+}
+
+check_duration 1 0.04 /0.0s
+check_duration 1 3.04 /3.0s
+check_duration 1 40.0 /40.0s
+check_duration 1 59.94 /59.9s
+check_duration 1 59.97 /1m0.0s
+check_duration 1 61.5 /1m1.5s
+check_duration 1 73.0 /1m13.0s
+check_duration 1 119.97 /2m0.0s
+check_duration 1 3599.99 /60m0.0s
+check_duration 2 59.996 /1m0.00s
+check_duration 2 0.02 /0.02s
+check_duration 0 1.4 /1s
+check_duration 0 59.6 /1m0s
+check_duration 0 119.5 /2m0s
+
+print -r -- "$tests tests, $failures failures"
+(( failures == 0 ))

plugins/timer/timer.plugin.zsh

@@ -6,8 +6,14 @@ __timer_current_time() {
 }
 
 __timer_format_duration() {
-  local mins=$(printf '%.0f' $(($(IFS='.' read int dec <<< "$1"; echo $int) / 60)))
-  local secs=$(printf "%.${TIMER_PRECISION:-1}f" $(($1 - 60 * mins)))
+  local -i precision=${TIMER_PRECISION:-1}
+  local -i scale=$(( 10 ** precision ))
+  # Round to the displayed precision before splitting off the minutes,
+  # so that e.g. 59.97s is shown as 1m0.0s instead of 60.0s
+  local -i units
+  (( units = $1 * scale + 0.5 ))
+  local -i mins=$(( units / (60 * scale) ))
+  local secs=$(printf "%.${precision}f" $(( (units - 60 * scale * mins) / (scale * 1.0) )))
   local duration_str=$(echo "${mins}m${secs}s")
   local format="${TIMER_FORMAT:-/%d}"
   echo "${format//\%d/${duration_str#0m}}"