refactor: use argv-iterator (#16)

privatenumber · Oct 31, 2022 · 9d2fe79 · 9d2fe79
1 parent 2baa4ce
commit 9d2fe79
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Showing 5 changed files with 284 additions and 288 deletions.
diff --git a/src/argv-iterator.ts b/src/argv-iterator.ts
@@ -0,0 +1,145 @@
+export const DOUBLE_DASH = '--';
+
+type BreakIteration = false;
+
+type onValueCallbackType = (
+ value?: string,
+ index?: number,
+) => void | BreakIteration;
+
+type onFlag = (
+ name: string,
+ value: string | undefined,
+ index: number,
+) => void | BreakIteration | onValueCallbackType;
+
+type onArgument = (
+ args: string[],
+ index: number,
+ isEoF?: boolean,
+) => void | BreakIteration;
+
+const valueDelimiterPattern = /[.:=]/;
+
+const isFlagPattern = /^-{1,2}[\da-z]/i;
+
+const parseFlagArgv = (
+ flagArgv: string,
+): [
+ flagName: string,
+ flagValue: string | undefined,
+ isAlias: boolean,
+] | undefined => {
+ if (!isFlagPattern.test(flagArgv)) {
+ return;
+ }
+
+ const isAlias = !flagArgv.startsWith(DOUBLE_DASH);
+ let flagName = flagArgv.slice(isAlias ? 1 : 2);
+
+ let flagValue;
+
+ const hasValueDalimiter = flagName.match(valueDelimiterPattern);
+ if (hasValueDalimiter?.index) {
+ const equalIndex = hasValueDalimiter.index;
+ flagValue = flagName.slice(equalIndex + 1);
+ flagName = flagName.slice(0, equalIndex);
+ }
+
+ return [flagName, flagValue, isAlias];
+};
+
+export const argvIterator = (
+ argv: string[],
+ callbacks: {
+ onFlag?: onFlag;
+ onArgument?: onArgument;
+ },
+) => {
+ let onValueCallback: undefined | onValueCallbackType;
+
+ const triggerCallback = (
+ value?: string,
+ index?: number,
+ ) => {
+ if (!onValueCallback) {
+ return true;
+ }
+
+ const result = onValueCallback(value, index);
+ onValueCallback = undefined;
+ return result;
+ };
+
+ ARGV_ITERATION:
+ for (let i = 0; i < argv.length; i += 1) {
+ const argvElement = argv[i];
+
+ if (argvElement === DOUBLE_DASH) {
+ if (triggerCallback() === false) {
+ break;
+ }
+
+ const remaining = argv.slice(i + 1);
+ callbacks.onArgument?.(remaining, i, true);
+ break;
+ }
+
+ const parsedFlag = parseFlagArgv(argvElement);
+
+ if (parsedFlag) {
+ if (triggerCallback() === false) {
+ break;
+ }
+
+ if (!callbacks.onFlag) {
+ continue;
+ }
+
+ const [flagName, flagValue, isAlias] = parsedFlag;
+
+ if (isAlias) {
+ for (let j = 0; j < flagName.length; j += 1) {
+ const alias = flagName[j];
+ const isLastAlias = j === flagName.length - 1;
+ const result = callbacks.onFlag(
+ alias,
+ isLastAlias ? flagValue : undefined,
+ i,
+ );
+
+ if (result === false) {
+ break ARGV_ITERATION;
+ } else if (typeof result === 'function') {
+ onValueCallback = result;
+ }
+ }
+ } else {
+ const result = callbacks.onFlag(
+ flagName,
+ flagValue,
+ i,
+ );
+
+ if (result === false) {
+ break;
+ } else if (typeof result === 'function') {
+ onValueCallback = result;
+ }
+ }
+ } else {
+ const result = triggerCallback(argvElement, i);
+ if (
+ result === false
+ || (
+ result === true // no callback set
+ && callbacks.onArgument?.([argvElement], i) === false
+ )
+ ) {
+ break;
+ }
+ }
+ }
+
+ triggerCallback();
+};
diff --git a/src/type-flag.ts b/src/type-flag.ts
@@ -1,22 +1,18 @@
 import type {
  Flags,
- FlagTypeOrSchema,
  ParsedFlags,
  TypeFlag,
 } from './types';
 import {
- DOUBLE_DASH,
- kebabToCamel,
- createFlagsObject,
- mapAliases,
- parseFlagArgv,
+ createRegistry,
  normalizeBoolean,
  applyParser,
- setDefaultFlagValues,
- parseFlagType,
  hasOwn,
- getOwn,
 } from './utils';
+import {
+ argvIterator,
+ DOUBLE_DASH,
+} from './argv-iterator';
 
 /**
 type-flag: typed argv parser
@@ -46,130 +42,55 @@ export const typeFlag = <Schemas extends Flags>(
  } = {},
 ) => {
  const { ignoreUnknown } = options;
- const aliasesMap = mapAliases(schemas);
- const parsed: ParsedFlags<Record<string, unknown>> = {
- flags: createFlagsObject(schemas),
- unknownFlags: {},
- _: Object.assign([], {
- [DOUBLE_DASH]: [],
- }),
- };
-
- let setValueOnPreviousFlag: undefined | ((value?: string | boolean) => void);
-
- const setKnown = (
- flagName: string,
- flagSchema: FlagTypeOrSchema,
- flagValue: any,
- ) => {
- const [flagType] = parseFlagType(flagSchema);
-
- flagValue = normalizeBoolean(flagType, flagValue);
-
- setValueOnPreviousFlag = (value) => {
- const parsedValue = applyParser(flagType, value || '');
- const flagsArray = parsed.flags[flagName];
- if (Array.isArray(flagsArray)) {
- flagsArray.push(parsedValue);
+ const [flagRegistry, flags] = createRegistry(schemas);
+ const unknownFlags: ParsedFlags['unknownFlags'] = {};
+ const _ = [] as unknown as ParsedFlags['_'];
+ _[DOUBLE_DASH] = [];
+
+ argvIterator(argv, {
+ onFlag(name, explicitValue, index) {
+ if (hasOwn(flagRegistry, name)) {
+ const [parser, values] = flagRegistry[name];
+ const flagValue = normalizeBoolean(parser, explicitValue);
+ const getFollowingValue = (value?: string | boolean) => {
+ values.push(
+ applyParser(parser, value || ''),
+ );
+ };
+
+ return (
+ flagValue === undefined
+ ? getFollowingValue
+ : getFollowingValue(flagValue)
+ );
+ } if (ignoreUnknown) {
+ _.push(argv[index]);
  } else {
- parsed.flags[flagName] = parsedValue;
- }
-
- setValueOnPreviousFlag = undefined;
- };
-
- if (flagValue !== undefined) {
- setValueOnPreviousFlag(flagValue);
- }
- };
-
- const setUnknown = (
- flagName: string,
- flagValue: any,
- ) => {
- if (!hasOwn(parsed.unknownFlags, flagName)) {
- parsed.unknownFlags[flagName] = [];
- }
-
- if (flagValue === undefined) {
- flagValue = true;
- }
-
- parsed.unknownFlags[flagName].push(flagValue);
- };
-
- for (let i = 0; i < argv.length; i += 1) {
- const argvElement = argv[i];
-
- if (argvElement === DOUBLE_DASH) {
- const remainingArgs = argv.slice(i + 1);
- parsed._[DOUBLE_DASH] = remainingArgs;
- parsed._.push(...remainingArgs);
- break;
- }
-
- const parsedFlag = parseFlagArgv(argvElement);
- if (parsedFlag) {
- if (setValueOnPreviousFlag) {
- setValueOnPreviousFlag();
- }
-
- const [flagName, flagValue, isAlias] = parsedFlag;
-
- if (isAlias) {
- for (let j = 0; j < flagName.length; j += 1) {
- const alias = flagName[j];
- const hasAlias = getOwn(aliasesMap, alias);
- const isLastAlias = j === flagName.length - 1;
-
- if (hasAlias) {
- setKnown(
- hasAlias.name,
- hasAlias.schema,
- isLastAlias ? flagValue : true,
- );
- } else if (ignoreUnknown) {
- parsed._.push(argvElement);
- } else {
- setUnknown(alias, isLastAlias ? flagValue : true);
- }
- }
- continue;
- }
-
- let name = flagName;
- let flagSchema = getOwn(schemas, flagName);
- if (!flagSchema) {
- const camelized = kebabToCamel(flagName);
- flagSchema = getOwn(schemas, camelized);
-
- if (flagSchema) {
- name = camelized;
+ if (!hasOwn(unknownFlags, name)) {
+ unknownFlags[name] = [];
  }
- }
 
- if (flagSchema) {
- setKnown(name, flagSchema, flagValue);
- } else if (ignoreUnknown) {
- parsed._.push(argvElement);
- } else {
- setUnknown(flagName, flagValue);
+ unknownFlags[name].push(
+ explicitValue === undefined ? true : explicitValue,
+ );
  }
- } else if (setValueOnPreviousFlag) { // Not a flag, but expecting a value
- setValueOnPreviousFlag(argvElement);
- } else { // Unexpected value
- parsed._.push(argvElement);
- }
- }
+ },
 
- if (setValueOnPreviousFlag) {
- setValueOnPreviousFlag();
- }
+ onArgument(args, _index, isEoF) {
+ _.push(...args);
 
- setDefaultFlagValues(schemas, parsed.flags);
+ if (isEoF) {
+ _[DOUBLE_DASH] = args;
+ }
+ },
+ });
 
  type Result = TypeFlag<Schemas>;
- return parsed as {
+ return {
+ flags,
+ unknownFlags,
+ _,
+ } as {
  // This exposes the content of "TypeFlag<T>" in type hints
  [Key in keyof Result]: Result[Key];
  };

diff --git a/src/types.ts b/src/types.ts
@@ -1,4 +1,4 @@
-import { DOUBLE_DASH } from './utils';
+import type { DOUBLE_DASH } from './argv-iterator';
 
 export type TypeFunction<ReturnType = any> = (value: any) => ReturnType;
 
@@ -93,7 +93,9 @@ export type InferFlagType<
 
 export type ParsedFlags<Schemas = Record<string, unknown>> = {
  flags: Schemas;
- unknownFlags: Record<string, (string | boolean)[]>;
+ unknownFlags: {
+ [flagName: string]: (string | boolean)[];
+ };
  _: string[] & {
  [DOUBLE_DASH]: string[];
  };