New: --max-parallel option

bin/common/parse-cli-args.js

@@ -79,6 +79,7 @@ class ArgumentSet {
     constructor(initialValues, options) {
         this.continueOnError = false
         this.groups = []
+        this.maxParallel = 0
         this.printLabel = false
         this.printName = false
         this.race = false
@@ -123,6 +124,11 @@ function parseCLIArgsCore(set, args) {    // eslint-disable-line complexity
                 set.rest = args.slice(1 + i)
                 break LOOP
 
+            case "--color":
+            case "--no-color":
+                // do nothing.
+                break
+
             case "-c":
             case "--continue-on-error":
                 set.continueOnError = true
@@ -147,9 +153,11 @@ function parseCLIArgsCore(set, args) {    // eslint-disable-line complexity
                 set.silent = true
                 break
 
-            case "--color":
-            case "--no-color":
-                // do nothing.
+            case "--max-parallel":
+                set.maxParallel = parseInt(args[++i], 10)
+                if (!Number.isFinite(set.maxParallel) || set.maxParallel <= 0) {
+                    throw new Error(`Invalid Option: --max-parallel ${args[i]}`)
+                }
                 break
 
             case "-s":
@@ -205,9 +213,11 @@ function parseCLIArgsCore(set, args) {    // eslint-disable-line complexity
     }
 
     if (!set.parallel && set.race) {
-        throw new Error(`Invalid Option: ${
-            args.indexOf("--race") !== -1 ? "race" : "r"
-        } (without parallel)`)
+        const race = args.indexOf("--race") !== -1 ? "race" : "r"
+        throw new Error(`Invalid Option: ${race} (without parallel)`)
+    }
+    if (!set.parallel && set.maxParallel !== 0) {
+        throw new Error("Invalid Option: --max-parallel (without parallel)")
     }
 
     return set

bin/npm-run-all/help.js

@@ -31,6 +31,8 @@ Options:
                                other/subsequent tasks even if a task threw an
                                error. 'npm-run-all' itself will exit with
                                non-zero code if one or more tasks threw error(s)
+    --max-parallel <number>  - Set the maximum number of parallelism. Default is
+                               unlimited.
     -l, --print-label  - - - - Set the flag to print the task name as a prefix
                                on each line of output. Tools in tasks may stop
                                coloring their output if this option was given.

bin/npm-run-all/main.js

@@ -42,6 +42,7 @@ module.exports = function npmRunAll(args, stdout, stderr) {
                         stderr,
                         stdin,
                         parallel: group.parallel,
+                        maxParallel: argv.maxParallel,
                         continueOnError: argv.continueOnError,
                         printLabel: argv.printLabel,
                         printName: argv.printName,

bin/run-p/help.js

@@ -31,6 +31,8 @@ Options:
                                even if a task threw an error. 'run-p' itself
                                will exit with non-zero code if one or more tasks
                                threw error(s).
+    --max-parallel <number>  - Set the maximum number of parallelism. Default is
+                               unlimited.
     -l, --print-label  - - - - Set the flag to print the task name as a prefix
                                on each line of output. Tools in tasks may stop
                                coloring their output if this option was given.

bin/run-p/main.js

@@ -42,6 +42,7 @@ module.exports = function npmRunAll(args, stdout, stderr) {
                 stderr,
                 stdin,
                 parallel: group.parallel,
+                maxParallel: argv.maxParallel,
                 continueOnError: argv.continueOnError,
                 printLabel: argv.printLabel,
                 printName: argv.printName,

docs/node-api.md

@@ -45,6 +45,9 @@ Run npm-scripts.
   - **options.parallel** `boolean` --
     The flag to run scripts in parallel.
     Default is `false`.
+  - **options.maxParallel** `number` --
+    The maximum number of parallelism.
+    Default is `Number.POSITIVE_INFINITY`.
   - **options.packageConfig** `object|null` --
     The map-like object to overwrite package configs.
     Keys are package names.

docs/npm-run-all.md

@@ -36,6 +36,8 @@ Options:
                                other/subsequent tasks even if a task threw an
                                error. 'npm-run-all' itself will exit with
                                non-zero code if one or more tasks threw error(s)
+    --max-parallel <number>  - Set the maximum number of parallelism. Default is
+                               unlimited.
     -l, --print-label  - - - - Set the flag to print the task name as a prefix
                                on each line of output. Tools in tasks may stop
                                coloring their output if this option was given.
@@ -109,7 +111,7 @@ npm-run-all clean lint --parallel watch:html watch:js
 ```
 
 1. First, this runs `clean` and `lint` sequentially / serially.
-2. Next, runs `watch:html` and `watch:js` in parallell.
+2. Next, runs `watch:html` and `watch:js` in parallel.
 
 ```
 npm-run-all a b --parallel c d --sequential e f --parallel g h i
@@ -121,9 +123,9 @@ npm-run-all a b --parallel c d --serial e f --parallel g h i
 ```
 
 1. First, runs `a` and `b` sequentially / serially.
-2. Second, runs `c` and `d` in parallell.
+2. Second, runs `c` and `d` in parallel.
 3. Third, runs `e` and `f` sequentially / serially.
-4. Lastly, runs `g`, `h`, and `i` in parallell.
+4. Lastly, runs `g`, `h`, and `i` in parallel.
 
 ### Glob-like pattern matching for script names
 

docs/run-p.md

@@ -35,6 +35,8 @@ Options:
                                even if a task threw an error. 'run-p' itself
                                will exit with non-zero code if one or more tasks
                                threw error(s).
+    --max-parallel <number>  - Set the maximum number of parallelism. Default is
+                               unlimited.
     -l, --print-label  - - - - Set the flag to print the task name as a prefix
                                on each line of output. Tools in tasks may stop
                                coloring their output if this option was given.

lib/index.js

@@ -13,8 +13,7 @@
 const shellQuote = require("shell-quote")
 const matchTasks = require("./match-tasks")
 const readPackageJson = require("./read-package-json")
-const runTasksInParallel = require("./run-tasks-in-parallel")
-const runTasksInSequencial = require("./run-tasks-in-sequencial")
+const runTasks = require("./run-tasks")
 
 //------------------------------------------------------------------------------
 // Helpers
@@ -204,28 +203,34 @@ function maxLength(length, name) {
  *   A promise object which becomes fullfilled when all npm-scripts are completed.
  */
 module.exports = function npmRunAll(patternOrPatterns, options) {
-    const parallel = Boolean(options && options.parallel)
     const stdin = (options && options.stdin) || null
     const stdout = (options && options.stdout) || null
     const stderr = (options && options.stderr) || null
     const taskList = (options && options.taskList) || null
     const config = (options && options.config) || null
     const packageConfig = (options && options.packageConfig) || null
     const args = (options && options.arguments) || []
+    const parallel = Boolean(options && options.parallel)
     const silent = Boolean(options && options.silent)
     const continueOnError = Boolean(options && options.continueOnError)
     const printLabel = Boolean(options && options.printLabel)
     const printName = Boolean(options && options.printName)
     const race = Boolean(options && options.race)
+    const maxParallel = parallel ? ((options && options.maxParallel) || 0) : 1
     try {
         const patterns = parsePatterns(patternOrPatterns, args)
         if (patterns.length === 0) {
             return Promise.resolve(null)
         }
-
         if (taskList != null && Array.isArray(taskList) === false) {
             throw new Error("Invalid options.taskList")
         }
+        if (typeof maxParallel !== "number" || !(maxParallel >= 0)) {
+            throw new Error("Invalid options.maxParallel")
+        }
+        if (!parallel && race) {
+            throw new Error("Invalid options.race")
+        }
 
         const prefixOptions = [].concat(
             silent ? ["--silent"] : [],
@@ -243,7 +248,6 @@ module.exports = function npmRunAll(patternOrPatterns, options) {
             .then(x => {
                 const tasks = matchTasks(x.taskList, patterns)
                 const labelWidth = tasks.reduce(maxLength, 0)
-                const runTasks = parallel ? runTasksInParallel : runTasksInSequencial
 
                 return runTasks(tasks, {
                     stdin,
@@ -260,6 +264,7 @@ module.exports = function npmRunAll(patternOrPatterns, options) {
                     printName,
                     packageInfo: x.packageInfo,
                     race,
+                    maxParallel,
                 })
             })
     }