feat: add bun handler (#51)

* add bun handler

* update

Author: AmirSa12

bin/handlers/bun-handler.ts

@@ -1,5 +1,194 @@
 import type { PackageManagerCompletion } from '../package-manager-completion.js';
+import { stripAnsiEscapes, type ParsedOption } from '../utils/text-utils.js';
+import {
+  LazyCommand,
+  OptionHandlers,
+  commonOptionHandlers,
+  setupLazyOptionLoading,
+  setupCommandArguments,
+  safeExec,
+  safeExecSync,
+} from '../utils/shared.js';
+
+const COMMANDS_SECTION_RE = /^Commands:\s*$/i;
+const FLAGS_SECTION_RE = /^Flags:\s*$/i;
+const SECTION_END_RE = /^(Examples|Full documentation|Learn more)/i;
+const COMMAND_VALIDATION_RE = /^[a-z][a-z0-9-]*$/;
+const BUN_OPTION_RE =
+  /^\s*(?:-([a-zA-Z]),?\s*)?--([a-z][a-z0-9-]*)(?:=<[^>]+>)?\s+(.+)$/;
+const MAIN_COMMAND_RE = /^  ([a-z][a-z0-9-]*)\s+(.+)$/;
+const CONTINUATION_COMMAND_RE = /^\s{12,}([a-z][a-z0-9-]*)\s+(.+)$/;
+const EMPTY_LINE_FOLLOWED_BY_NON_COMMAND_RE = /^\s+[a-z]/;
+const DESCRIPTION_SPLIT_RE = /\s{2,}/;
+const CAPITAL_LETTER_START_RE = /^[A-Z]/;
+const LINE_SPLIT_RE = /\r?\n/;
+
+function toLines(text: string): string[] {
+  return stripAnsiEscapes(text).split(LINE_SPLIT_RE);
+}
+
+function findSectionStart(lines: string[], header: RegExp): number {
+  for (let i = 0; i < lines.length; i++) {
+    if (header.test(lines[i].trim())) return i + 1;
+  }
+  return -1;
+}
+
+const bunOptionHandlers: OptionHandlers = {
+  ...commonOptionHandlers,
+
+  backend(complete) {
+    complete('clonefile', ' ');
+    complete('hardlink', ' ');
+    complete('symlink', ' ');
+    complete('copyfile', ' ');
+  },
+
+  linker(complete) {
+    complete('isolated', ' ');
+    complete('hoisted', ' ');
+  },
+
+  omit(complete) {
+    complete('dev', ' ');
+    complete('optional', ' ');
+    complete('peer', ' ');
+  },
+
+  shell(complete) {
+    complete('bun', ' ');
+    complete('system', ' ');
+  },
+
+  'unhandled-rejections'(complete) {
+    complete('strict', ' ');
+    complete('throw', ' ');
+    complete('warn', ' ');
+    complete('none', ' ');
+    complete('warn-with-error-code', ' ');
+  },
+};
+
+export function parseBunHelp(helpText: string): Record<string, string> {
+  const lines = toLines(helpText);
+
+  const startIndex = findSectionStart(lines, COMMANDS_SECTION_RE);
+  if (startIndex === -1) return {};
+
+  const commands: Record<string, string> = {};
+
+  for (let i = startIndex; i < lines.length; i++) {
+    const line = lines[i];
+
+    // stop when we hit Flags section or empty line followed by non-command content
+    if (
+      FLAGS_SECTION_RE.test(line.trim()) ||
+      (line.trim() === '' &&
+        i + 1 < lines.length &&
+        !lines[i + 1].match(EMPTY_LINE_FOLLOWED_BY_NON_COMMAND_RE))
+    ) {
+      break;
+    }
+
+    if (!line.trim()) continue;
+
+    // main command row
+    const main = line.match(MAIN_COMMAND_RE);
+    if (main) {
+      const [, command, rest] = main;
+      if (COMMAND_VALIDATION_RE.test(command)) {
+        const parts = rest.split(DESCRIPTION_SPLIT_RE);
+        let desc = parts[parts.length - 1];
+
+        if (desc && CAPITAL_LETTER_START_RE.test(desc)) {
+          commands[command] = desc.trim();
+        } else if (parts.length > 1) {
+          for (const p of parts) {
+            if (CAPITAL_LETTER_START_RE.test(p)) {
+              commands[command] = p.trim();
+              break;
+            }
+          }
+        }
+      }
+    }
+
+    const cont = line.match(CONTINUATION_COMMAND_RE);
+    if (cont) {
+      const [, command, description] = cont;
+      if (COMMAND_VALIDATION_RE.test(command)) {
+        commands[command] = description.trim();
+      }
+    }
+  }
+
+  return commands;
+}
+
+export async function getBunCommandsFromMainHelp(): Promise<
+  Record<string, string>
+> {
+  const output = await safeExec('bun --help');
+  return output ? parseBunHelp(output) : {};
+}
+
+export function parseBunOptions(
+  helpText: string,
+  { flagsOnly = true }: { flagsOnly?: boolean } = {}
+): ParsedOption[] {
+  const lines = toLines(helpText);
+  const out: ParsedOption[] = [];
+
+  const start = findSectionStart(lines, FLAGS_SECTION_RE);
+  if (start === -1) return out;
+
+  for (let i = start; i < lines.length; i++) {
+    const line = lines[i];
+    if (SECTION_END_RE.test(line.trim())) break;
+
+    const m = line.match(BUN_OPTION_RE);
+    if (!m) continue;
+
+    const [, short, long, desc] = m;
+    const takesValue = line.includes('=<'); // bun shows value as --opt=<val>
+    if (flagsOnly && takesValue) continue;
+
+    out.push({
+      short: short || undefined,
+      long,
+      desc: desc.trim(),
+    });
+  }
+
+  return out;
+}
+
+function loadBunOptionsSync(cmd: LazyCommand, command: string): void {
+  const output = safeExecSync(`bun ${command} --help`);
+  if (!output) return;
+
+  const options = parseBunOptions(output, { flagsOnly: false });
+
+  for (const { long, short, desc } of options) {
+    const exists = cmd.optionsRaw?.get?.(long);
+    if (exists) continue;
+
+    const handler = bunOptionHandlers[long];
+    if (handler) cmd.option(long, desc, handler, short);
+    else cmd.option(long, desc, short);
+  }
+}
 
 export async function setupBunCompletions(
   completion: PackageManagerCompletion
-): Promise<void> {}
+): Promise<void> {
+  try {
+    const commands = await getBunCommandsFromMainHelp();
+
+    for (const [command, description] of Object.entries(commands)) {
+      const c = completion.command(command, description);
+      setupCommandArguments(c, command, 'bun');
+      setupLazyOptionLoading(c, command, 'bun', loadBunOptionsSync);
+    }
+  } catch {}
+}