BREAKING(io): remove readDelim() (#6052)

* BREAKING(io/unstable): remove `readStringDelim()`

* BREAKING(io/unstable): remove `readDelim()`

io/deno.json

@@ -9,7 +9,6 @@
     "./limited-reader": "./limited_reader.ts",
     "./multi-reader": "./multi_reader.ts",
     "./read-all": "./read_all.ts",
-    "./read-delim": "./read_delim.ts",
     "./reader-from-stream-reader": "./reader_from_stream_reader.ts",
     "./string-reader": "./string_reader.ts",
     "./string-writer": "./string_writer.ts",

io/mod.ts

@@ -22,7 +22,6 @@ export * from "./iterate_reader.ts";
 export * from "./limited_reader.ts";
 export * from "./multi_reader.ts";
 export * from "./read_all.ts";
-export * from "./read_delim.ts";
 export * from "./reader_from_stream_reader.ts";
 export * from "./string_reader.ts";
 export * from "./string_writer.ts";

io/read_delim.ts

@@ -1,103 +0,0 @@
-// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
-// This module is browser compatible.
-
-import { concat } from "@std/bytes/concat";
-import type { Reader } from "./types.ts";
-
-/** Generate longest proper prefix which is also suffix array. */
-function createLPS(pat: Uint8Array): Uint8Array {
-  const lps = new Uint8Array(pat.length);
-  lps[0] = 0;
-  let prefixEnd = 0;
-  let i = 1;
-  while (i < lps.length) {
-    if (pat[i] === pat[prefixEnd]) {
-      prefixEnd++;
-      lps[i] = prefixEnd;
-      i++;
-    } else if (prefixEnd === 0) {
-      lps[i] = 0;
-      i++;
-    } else {
-      prefixEnd = lps[prefixEnd - 1]!;
-    }
-  }
-  return lps;
-}
-
-/**
- * Read delimited bytes from a {@linkcode Reader} through an
- * {@linkcode AsyncIterableIterator} of {@linkcode Uint8Array}.
- *
- * @example Usage
- * ```ts
- * import { readDelim } from "@std/io/read-delim";
- * import { assert } from "@std/assert/assert"
- *
- * using fileReader = await Deno.open("README.md");
- *
- * for await (const chunk of readDelim(fileReader, new TextEncoder().encode("\n"))) {
- *   assert(chunk instanceof Uint8Array);
- * }
- * ```
- *
- * @param reader The reader to read from
- * @param delim The delimiter to read until
- * @returns The {@linkcode AsyncIterableIterator} of {@linkcode Uint8Array}s.
- *
- * @deprecated Use
- * {@linkcode https://jsr.io/@std/streams/doc/byte-slice-stream/~/ByteSliceStream | ByteSliceStream}
- * instead. This will be removed in 0.225.0.
- */
-export async function* readDelim(
-  reader: Reader,
-  delim: Uint8Array,
-): AsyncIterableIterator<Uint8Array> {
-  // Avoid unicode problems
-  const delimLen = delim.length;
-  const delimLPS = createLPS(delim);
-  let chunks = new Uint8Array();
-  const bufSize = Math.max(1024, delimLen + 1);
-
-  // Modified KMP
-  let inspectIndex = 0;
-  let matchIndex = 0;
-  while (true) {
-    const inspectArr = new Uint8Array(bufSize);
-    const result = await reader.read(inspectArr);
-    if (result === null) {
-      // Yield last chunk.
-      yield chunks;
-      return;
-    } else if (result < 0) {
-      // Discard all remaining and silently fail.
-      return;
-    }
-    chunks = concat([chunks, inspectArr.slice(0, result)]);
-    let localIndex = 0;
-    while (inspectIndex < chunks.length) {
-      if (inspectArr[localIndex] === delim[matchIndex]) {
-        inspectIndex++;
-        localIndex++;
-        matchIndex++;
-        if (matchIndex === delimLen) {
-          // Full match
-          const matchEnd = inspectIndex - delimLen;
-          const readyBytes = chunks.slice(0, matchEnd);
-          yield readyBytes;
-          // Reset match, different from KMP.
-          chunks = chunks.slice(inspectIndex);
-          inspectIndex = 0;
-          matchIndex = 0;
-        }
-      } else {
-        if (matchIndex === 0) {
-          inspectIndex++;
-          localIndex++;
-        } else {
-          matchIndex = delimLPS[matchIndex - 1]!;
-        }
-      }
-    }
-  }
-}