nandi.uk
Fork of daniellemaywood.uk/gleam — Wasm codegen work
Add disjoint string prefix with guard test
author
John Downey
committer
Louis Pilfold
date
(Jul 7, 2026, 2:19 PM +0100)
commit
80a23835
80a238357f5d6fd61344d602790a9db223ebae73
parent
bbba2eaf
bbba2eafa328ddbec8560c21aba1d75dff0c7240
+62
+30
compiler-core/src/javascript/tests/snapshots/gleam_core__javascript__tests__strings__disjoint_string_prefixes_with_guard.snap
+30
compiler-core/src/javascript/tests/snapshots/gleam_core__javascript__tests__strings__disjoint_string_prefixes_with_guard.snap
···
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---
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source: compiler-core/src/javascript/tests/strings.rs
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expression: "\npub fn classify(input: String) -> String {\n case input {\n \"aa\" <> rest if rest == \"x\" -> rest\n \"b\" <> _ -> \"b-start\"\n _ -> \"other\"\n }\n}\n"
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---
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----- SOURCE CODE
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pub fn classify(input: String) -> String {
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case input {
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"aa" <> rest if rest == "x" -> rest
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"b" <> _ -> "b-start"
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_ -> "other"
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}
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}
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----- COMPILED JAVASCRIPT
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export function classify(input) {
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if (input.startsWith("aa")) {
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let rest = input.slice(2);
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if (rest === "x") {
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return rest;
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} else {
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return "other";
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}
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} else if (input.charCodeAt(0) === 98) {
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return "b-start";
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} else {
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return "other";
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}
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}
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compiler-core/src/javascript/tests/strings.rs
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compiler-core/src/javascript/tests/strings.rs
···
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"#,
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);
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}
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// https://github.com/gleam-lang/gleam/issues/5856
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#[test]
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fn disjoint_string_prefixes_with_guard() {
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assert_js!(
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r#"
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pub fn classify(input: String) -> String {
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case input {
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"aa" <> rest if rest == "x" -> rest
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"b" <> _ -> "b-start"
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_ -> "other"
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}
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}
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"#,
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);
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}
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test/language/test/language/string_pattern_matching_test.gleam
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test/language/test/language/string_pattern_matching_test.gleam
···
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assert classify("🫥z") == "z"
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assert classify("abc") == "other"
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}
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// https://github.com/gleam-lang/gleam/issues/5856
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pub fn disjoint_string_prefixes_with_guard_test() {
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let classify = fn(input: String) -> String {
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case input {
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"aa" <> rest if rest == "x" -> rest
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"b" <> _ -> "b-start"
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_ -> "other"
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}
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}
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assert classify("aax") == "x"
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assert classify("aay") == "other"
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assert classify("bcd") == "b-start"
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assert classify("zzz") == "other"
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}