regExpEscape -> escape

regexp/regexp_escape.ts → regexp/escape.ts

@@ -65,17 +65,17 @@ const RX_REGEXP_ESCAPE = new RegExp(
  *
  * @example
  * ```ts
- * import { regExpEscape } from "https://deno.land/std@$STD_VERSION/regexp/mod.ts";
+ * import { escape } from "https://deno.land/std@$STD_VERSION/regexp/mod.ts";
  * import { assertEquals, assertMatch, assertNotMatch } from "https://deno.land/std@$STD_VERSION/testing/asserts.ts";
  *
- * const re = new RegExp(`^${regExpEscape(".")}$`, "u");
+ * const re = new RegExp(`^${escape(".")}$`, "u");
  *
  * assertEquals("^\\.$", re.source);
  * assertMatch(".", re);
  * assertNotMatch("a", re);
  * ```
  */
-export function regExpEscape(str: string) {
+export function escape(str: string) {
   return str.replaceAll(
     RX_REGEXP_ESCAPE,
     (m) => reservedCharMap[m as keyof typeof reservedCharMap],

regexp/escape_test.ts

@@ -0,0 +1,100 @@
+// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+
+import { escape } from "./escape.ts";
+import {
+  assertEquals,
+  assertMatch,
+  assertNotMatch,
+} from "../testing/asserts.ts";
+
+const ALL_ASCII =
+  "\x00\x01\x02\x03\x04\x05\x06\x07\b\t\n\v\f\r\x0E\x0F\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1A\x1B\x1C\x1D\x1E\x1F !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\x7F";
+const ALL_REGEXP_FLAGS = "gimsuy";
+
+Deno.test("regexp", async (t) => {
+  await t.step("escape", async (t) => {
+    await t.step("examples", async (t) => {
+      await t.step("`.` matches literal `.`", () => {
+        const re = new RegExp(`^${escape(".")}$`, "u");
+
+        assertEquals("^\\.$", re.source);
+        assertMatch(".", re);
+        assertNotMatch("a", re);
+      });
+      await t.step("`$` matches literal `$`", () => {
+        const re = new RegExp(`^${escape("$")}$`);
+
+        assertMatch("$", re);
+        assertNotMatch("", re);
+      });
+      await t.step("`*` matches literal `*`", () => {
+        const re = new RegExp(`^${escape("a*")}$`);
+
+        assertMatch("a*", re);
+        assertNotMatch("", re);
+        assertNotMatch("aaa", re);
+      });
+      await t.step("escapes work correctly within character class", () => {
+        const re = new RegExp(`^[${escape(".$*+[](){}|\\<>")}]$`);
+
+        assertMatch(".", re);
+        assertMatch("$", re);
+        assertMatch("*", re);
+        assertMatch("+", re);
+        assertMatch("[", re);
+        assertMatch("]", re);
+        assertMatch("(", re);
+        assertMatch(")", re);
+        assertMatch("{", re);
+        assertMatch("}", re);
+        assertMatch("|", re);
+        assertMatch("\\", re);
+        assertMatch("<", re);
+        assertMatch(">", re);
+
+        assertNotMatch("a", re);
+      });
+    });
+    await t.step("all ASCII", async (t) => {
+      await t.step("interpolates without erroring", async (t) => {
+        await t.step("outside character class", () => {
+          for (const char of ALL_ASCII) {
+            for (const flag of ALL_REGEXP_FLAGS) {
+              new RegExp(escape(char), flag);
+            }
+          }
+        });
+        await t.step("within character class", () => {
+          for (const char of ALL_ASCII) {
+            for (const flag of ALL_REGEXP_FLAGS) {
+              new RegExp(`[${escape(char)}]`, flag);
+            }
+          }
+        });
+        await t.step("matches self", () => {
+          for (const char of ALL_ASCII) {
+            for (const flag of ALL_REGEXP_FLAGS) {
+              assertMatch(char, new RegExp(`^${escape(char)}$`, flag));
+            }
+          }
+        });
+        await t.step("doesn't match any other chars", () => {
+          for (const char of ALL_ASCII) {
+            for (const flag of ALL_REGEXP_FLAGS) {
+              if (flag === "i") continue;
+
+              for (const char2 of ALL_ASCII) {
+                if (char2 === char) continue;
+
+                assertNotMatch(
+                  char2,
+                  new RegExp(`^${escape(char)}$`, flag),
+                );
+              }
+            }
+          }
+        });
+      });
+    });
+  });
+});

regexp/mod.ts

@@ -8,4 +8,4 @@
  * @module
  */
 
-export * from "./regexp_escape.ts";
+export * from "./escape.ts";