commit-check · shenxianpeng · Aug 6, 2026 · Aug 6, 2026 · Aug 6, 2026
@@ -1,39 +1,80 @@
-# demo.tape — Generate demo.gif with: brew install vhs && vhs docs/demo.tape
+# demo.tape — regenerate with `vhs assets/demo.tape` from the repository root.
+#
+# Needs vhs (https://github.com/charmbracelet/vhs) and commit-check on PATH.
+#
+# The hidden block below records inside a throwaway repository, so running this
+# never leaves stray branches behind in the repository you invoke it from.
 
-Output demo.gif
+Output assets/demo.gif
 
 Set Shell "zsh"
 
 Set FontSize 16
-Set Width 1000
-Set Height 550
+# The longest line a failure prints is the CC001 suggestion, at 131 columns.
+# This width measures 132 columns (checked with `tput cols` in the recorder,
+# not calculated — the glyph advance is 10.26px, not the 9.6px you get from
+# assuming 0.6em). Narrower breaks that line, and the URL above it, mid-word.
+Set Width 1400
+Set Height 600
 Set Theme "Dracula"
 Set Padding 24
 Set TypingSpeed 50ms
 Set PlaybackSpeed 1.0
 
-# --- Scene 1: Invalid commit message ---
-Type "echo 'add user login' | commit-check -m"
+Hide
+# The identity matters: without it the initial commit fails, the repository is
+# left with no commits at all, and every branch check then silently passes —
+# which is exactly how this demo once recorded a failing branch as clean.
+# ${DEMO_REPO:?} rather than a bare cd: when a command substitution produces
+# nothing, zsh reads `cd $(...)` as plain `cd` and goes to $HOME — so a failing
+# mktemp would have this git init a maintainer's home directory. The guard
+# aborts the chain instead.
+Type "DEMO_REPO=$(mktemp -d) && cd ${DEMO_REPO:?} && git init -q -b main . && git config user.name 'Dev' && git config user.email 'dev@example.com'"
+Enter
+Type "git commit -q --allow-empty -m 'feat: initial commit'"
+Enter
+Type "export PS1='%F{cyan}❯%f '"
+Enter
+Type "clear"
 Enter
 Sleep 2s
+Show
 
-# --- Scene 2: Valid commit message ---
-Type "echo 'feat: add user login' | commit-check -m"
+# --- A commit message that does not follow Conventional Commits ---
+Type "echo 'add user login' | commit-check -m"
 Enter
-Sleep 2s
+Sleep 4s
 
-# --- Scene 4: Invalid branch name ---
-Type "git checkout -b user-login"
+# --- The same message, fixed. A passing check prints nothing and exits 0, so
+#     the demo reports the result rather than showing an empty line. ---
+Type "echo 'feat: add user login' | commit-check -m && echo 'passed'"
 Enter
-Sleep 2s
-Type "commit-check -b"
+Sleep 3s
+
+Hide
+Type "clear"
 Enter
-Sleep 2s
+Show
 
-# --- Scene 5: Valid branch name ---
-Type "git checkout -b feature/user-login"
+# --- A branch name that does not follow Conventional Branch ---
+Type "git switch -c user-login"
 Enter
-Sleep 2s
+Sleep 1500ms
 Type "commit-check -b"
 Enter
-Sleep 2s
+Sleep 4s
+
+# --- The same branch, fixed ---
+Type "git switch -c feature/user-login"
+Enter
+Sleep 1500ms
+Type "commit-check -b && echo 'passed'"
+Enter
+Sleep 3s
+
+Hide
+# Leave no throwaway repository behind. The same guard applies: an unset or
+# empty DEMO_REPO aborts rather than handing rm -rf a bare path.
+Type "cd / && rm -rf ${DEMO_REPO:?}"
+Enter
+Show