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Diffstat (limited to 'src/js_ast.zig')
| -rw-r--r-- | src/js_ast.zig | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/src/js_ast.zig b/src/js_ast.zig index 90e3f2a9c..f3d941251 100644 --- a/src/js_ast.zig +++ b/src/js_ast.zig @@ -1849,6 +1849,23 @@ pub const E = struct { pub var empty = RegExp{ .value = "" }; + pub fn usesLookBehindAssertion(this: *const RegExp) bool { + var pat = this.pattern(); + while (pat.len > 0) { + const start = strings.indexOfChar(pat, '?') orelse return false; + if (start == 0) return false; + const l_paren = pat[start - 1]; + if (l_paren != '(' or pat.len < start + 1) return false; + const op = pat[start + 1]; + if (op == '<' or op == '=' or op == '!') { + return true; + } + pat = pat[start + 1 ..]; + } + + return false; + } + pub fn pattern(this: RegExp) string { // rewind until we reach the /foo/gim |