amadan
Hold shell.js's and transition.js's transition observers identical
Both files stay standalone, since a server sends their bytes as they are with no build step between. TestTheTwoTransitionObserversAreTheSame holds the WeakSet and the function identical but for its name, as strings_test.go holds the two fiestaWord copies, so an edit to one fails until the other matches.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
1 file changed,
+31
−0
check/shell_test.go+31 −0
diff --git a/check/shell_test.go b/check/shell_test.go| index af28071..726e702 100644 |
| --- a/check/shell_test.go |
| +++ b/check/shell_test.go |
| @@ -2,6 +2,7 @@ package check |
| import ( |
| "encoding/json" |
| + "strings" |
| "testing" |
| "amadan.net/rastrillo/fiesta/internal/nodetest" |
| @@ -60,3 +61,33 @@ func skippedTransitionsAreSwallowed(t *testing.T, script string) { |
| func TestTransitionJSSwallowsOnlyASkippedTransition(t *testing.T) { |
| skippedTransitionsAreSwallowed(t, "transition.js") |
| } |
| + |
| +// TestTheTwoTransitionObserversAreTheSame: shell.js and transition.js |
| +// each carry the code that swallows a skipped transition's rejection, |
| +// because each is a file a page loads on its own, with no build step |
| +// between this tree and the bytes a server sends. The price of two |
| +// copies is drift, so the two are held identical: the WeakSet and the |
| +// function, character for character, but for the function's name. |
| +func TestTheTwoTransitionObserversAreTheSame(t *testing.T) { |
| + shell := transitionObserver(t, "shell.js", "observeTransition") |
| + alone := transitionObserver(t, "transition.js", "observe") |
| + renamed := strings.ReplaceAll(shell, "function observeTransition(", "function observe(") |
| + if renamed != alone { |
| + t.Errorf("the transition observer differs between shell.js and transition.js:\n--- shell.js\n%s\n--- transition.js\n%s", shell, alone) |
| + } |
| +} |
| + |
| +// transitionObserver is one script's observer: the WeakSet declared |
| +// straight before it and the function itself. It fails the test when |
| +// the script has no such pair, so the comparison is never of nothing. |
| +func transitionObserver(t *testing.T, script, name string) string { |
| + t.Helper() |
| + const set = "var observed = new WeakSet();\n" |
| + js := string(shippedScript(t, script)) |
| + body := functionBody(js, name) |
| + at := strings.Index(js, set+strings.Repeat(" ", 2)+"function "+name+"(") |
| + if body == "" || at < 0 { |
| + t.Fatalf("%s has no %q followed by function %s", script, strings.TrimSpace(set), name) |
| + } |
| + return set + body |
| +} |