add ability to specify node executable for npm based formatters

CHANGES.md

@@ -12,6 +12,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 ## [Unreleased]
 ### Added
 * `ProcessRunner` has added some convenience methods so it can be used for maven testing. ([#1496](https://github.com/diffplug/spotless/pull/1496))
+* Allow to specify node executable for node-based formatters using `nodeExecutable` parameter ([#1500](https://github.com/diffplug/spotless/pull/1500))
 ### Fixed
 * The default list of type annotations used by `formatAnnotations` has had 8 more annotations from the Checker Framework added [#1494](https://github.com/diffplug/spotless/pull/1494)
 ### Changes

lib/src/main/java/com/diffplug/spotless/npm/EslintFormatterStep.java

@@ -94,9 +94,11 @@ private static class State extends NpmFormatterStepStateBase implements Serializ
 									"/com/diffplug/spotless/npm/common-serve.js",
 									"/com/diffplug/spotless/npm/eslint-serve.js"),
 							npmPathResolver.resolveNpmrcContent()),
-					projectDir,
-					buildDir,
-					npmPathResolver.resolveNpmExecutable());
+					new NpmFormatterStepLocations(
+							projectDir,
+							buildDir,
+							npmPathResolver.resolveNpmExecutable(),
+							npmPathResolver.resolveNodeExecutable()));
 			this.eslintConfig = localCopyFiles(requireNonNull(eslintConfig));
 		}
 
@@ -119,7 +121,7 @@ public FormatterFunc createFormatterFunc() {
 				FormattedPrinter.SYSOUT.print("creating formatter function (starting server)");
 				ServerProcessInfo eslintRestServer = npmRunServer();
 				EslintRestService restService = new EslintRestService(eslintRestServer.getBaseUrl());
-				return Closeable.ofDangerous(() -> endServer(restService, eslintRestServer), new EslintFilePathPassingFormatterFunc(projectDir, nodeModulesDir, eslintConfig, restService));
+				return Closeable.ofDangerous(() -> endServer(restService, eslintRestServer), new EslintFilePathPassingFormatterFunc(locations.projectDir(), nodeModulesDir, eslintConfig, restService));
 			} catch (IOException e) {
 				throw ThrowingEx.asRuntime(e);
 			}

lib/src/main/java/com/diffplug/spotless/npm/NodeExecutableResolver.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2023 DiffPlug
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.diffplug.spotless.npm;
+
+import java.io.File;
+import java.util.Optional;
+
+class NodeExecutableResolver {
+
+	private NodeExecutableResolver() {
+		// no instance
+	}
+
+	static String nodeExecutableName() {
+		String nodeName = "node";
+		if (PlatformInfo.normalizedOS() == PlatformInfo.OS.WINDOWS) {
+			nodeName += ".exe";
+		}
+		return nodeName;
+	}
+
+	static Optional<File> tryFindNextTo(File npmExecutable) {
+		if (npmExecutable == null) {
+			return Optional.empty();
+		}
+		File nodeExecutable = new File(npmExecutable.getParentFile(), nodeExecutableName());
+		if (nodeExecutable.exists() && nodeExecutable.isFile() && nodeExecutable.canExecute()) {
+			return Optional.of(nodeExecutable);
+		}
+		return Optional.empty();
+	}
+
+	public static String explainMessage() {
+		return "Spotless was unable to find a node executable.\n" +
+				"Either specify the node executable explicitly or make sure it can be found next to the npm executable.";
+	}
+}

lib/src/main/java/com/diffplug/spotless/npm/NpmFormatterStepLocations.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2023 DiffPlug
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.diffplug.spotless.npm;
+
+import static java.util.Objects.requireNonNull;
+
+import java.io.File;
+import java.io.Serializable;
+
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+
+class NpmFormatterStepLocations implements Serializable {
+
+	private static final long serialVersionUID = -1055408537924029969L;
+	@SuppressFBWarnings("SE_TRANSIENT_FIELD_NOT_RESTORED")
+	private final transient File projectDir;
+
+	@SuppressFBWarnings("SE_TRANSIENT_FIELD_NOT_RESTORED")
+	private final transient File buildDir;
+
+	@SuppressFBWarnings("SE_TRANSIENT_FIELD_NOT_RESTORED")
+	private final transient File npmExecutable;
+
+	@SuppressFBWarnings("SE_TRANSIENT_FIELD_NOT_RESTORED")
+	private final transient File nodeExecutable;
+
+	public NpmFormatterStepLocations(File projectDir, File buildDir, File npmExecutable, File nodeExecutable) {
+		this.projectDir = requireNonNull(projectDir);
+		this.buildDir = requireNonNull(buildDir);
+		this.npmExecutable = requireNonNull(npmExecutable);
+		this.nodeExecutable = requireNonNull(nodeExecutable);
+	}
+
+	public File projectDir() {
+		return projectDir;
+	}
+
+	public File buildDir() {
+		return buildDir;
+	}
+
+	public File npmExecutable() {
+		return npmExecutable;
+	}
+
+	public File nodeExecutable() {
+		return nodeExecutable;
+	}
+}

lib/src/main/java/com/diffplug/spotless/npm/NpmFormatterStepStateBase.java

@@ -48,23 +48,17 @@ abstract class NpmFormatterStepStateBase implements Serializable {
 	@SuppressFBWarnings("SE_TRANSIENT_FIELD_NOT_RESTORED")
 	public final transient File nodeModulesDir;
 
-	@SuppressFBWarnings("SE_TRANSIENT_FIELD_NOT_RESTORED")
-	private final transient File npmExecutable;
-
-	@SuppressFBWarnings("SE_TRANSIENT_FIELD_NOT_RESTORED")
-	public final transient File projectDir;
+	public final NpmFormatterStepLocations locations;
 
 	private final NpmConfig npmConfig;
 
 	private final String stepName;
 
-	protected NpmFormatterStepStateBase(String stepName, NpmConfig npmConfig, File projectDir, File buildDir, File npm) throws IOException {
+	protected NpmFormatterStepStateBase(String stepName, NpmConfig npmConfig, NpmFormatterStepLocations locations) throws IOException {
 		this.stepName = requireNonNull(stepName);
 		this.npmConfig = requireNonNull(npmConfig);
-		this.projectDir = requireNonNull(projectDir);
-		this.npmExecutable = npm;
-
-		NodeServerLayout layout = prepareNodeServer(buildDir);
+		this.locations = locations;
+		NodeServerLayout layout = prepareNodeServer(locations.buildDir());
 		this.nodeModulesDir = layout.nodeModulesDir();
 		this.packageJsonSignature = FileSignature.signAsList(layout.packageJsonFile());
 	}
@@ -88,7 +82,7 @@ private NodeServerLayout prepareNodeServer(File buildDir) throws IOException {
 	}
 
 	private void runNpmInstall(File npmProjectDir) throws IOException {
-		new NpmProcess(npmProjectDir, this.npmExecutable).install();
+		new NpmProcess(npmProjectDir, this.locations.npmExecutable(), this.locations.nodeExecutable()).install();
 	}
 
 	protected ServerProcessInfo npmRunServer() throws ServerStartException, IOException {
@@ -102,7 +96,7 @@ protected ServerProcessInfo npmRunServer() throws ServerStartException, IOExcept
 			final File serverPortFile = new File(this.nodeModulesDir, "server.port");
 			NpmResourceHelper.deleteFileIfExists(serverPortFile);
 			// start the http server in node
-			Process server = new NpmProcess(this.nodeModulesDir, this.npmExecutable).start();
+			Process server = new NpmProcess(this.nodeModulesDir, this.locations.npmExecutable(), this.locations.nodeExecutable()).start();
 
 			// await the readiness of the http server - wait for at most 60 seconds
 			try {

lib/src/main/java/com/diffplug/spotless/npm/NpmPathResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2020 DiffPlug
+ * Copyright 2020-2023 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,28 +16,67 @@
 package com.diffplug.spotless.npm;
 
 import java.io.File;
-import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
 
 public class NpmPathResolver {
 
 	private final File explicitNpmExecutable;
 
+	private final File explicitNodeExecutable;
+
 	private final File explicitNpmrcFile;
 
 	private final List<File> additionalNpmrcLocations;
 
-	public NpmPathResolver(File explicitNpmExecutable, File explicitNpmrcFile, File... additionalNpmrcLocations) {
+	public NpmPathResolver(File explicitNpmExecutable, File explicitNodeExecutable, File explicitNpmrcFile, List<File> additionalNpmrcLocations) {
 		this.explicitNpmExecutable = explicitNpmExecutable;
+		this.explicitNodeExecutable = explicitNodeExecutable;
 		this.explicitNpmrcFile = explicitNpmrcFile;
-		this.additionalNpmrcLocations = Arrays.asList(additionalNpmrcLocations);
+		this.additionalNpmrcLocations = Collections.unmodifiableList(new ArrayList<>(additionalNpmrcLocations));
 	}
 
+	/**
+	 * Finds the npm executable to use.
+	 * <br>
+	 * Either the explicit npm executable is returned, or - if an explicit node executable is configured - tries to find
+	 * the npm executable relative to the node executable.
+	 * Falls back to looking for npm on the user's system using {@link NpmExecutableResolver}
+	 *
+	 * @return the npm executable to use
+	 * @throws IllegalStateException if no npm executable could be found
+	 */
 	public File resolveNpmExecutable() {
-		return Optional.ofNullable(this.explicitNpmExecutable)
-				.orElseGet(() -> NpmExecutableResolver.tryFind()
-						.orElseThrow(() -> new IllegalStateException("Can't automatically determine npm executable and none was specifically supplied!\n\n" + NpmExecutableResolver.explainMessage())));
+		if (this.explicitNpmExecutable != null) {
+			return this.explicitNpmExecutable;
+		}
+		if (this.explicitNodeExecutable != null) {
+			File nodeExecutableCandidate = new File(this.explicitNodeExecutable.getParentFile(), NpmExecutableResolver.npmExecutableName());
+			if (nodeExecutableCandidate.canExecute()) {
+				return nodeExecutableCandidate;
+			}
+		}
+		return NpmExecutableResolver.tryFind()
+				.orElseThrow(() -> new IllegalStateException("Can't automatically determine npm executable and none was specifically supplied!\n\n" + NpmExecutableResolver.explainMessage()));
+	}
+
+	/**
+	 * Finds the node executable to use.
+	 * <br>
+	 * Either the explicit node executable is returned, or tries to find the node executable relative to the npm executable
+	 * found by {@link #resolveNpmExecutable()}.
+	 * @return the node executable to use
+	 * @throws IllegalStateException if no node executable could be found
+	 */
+	public File resolveNodeExecutable() {
+		if (this.explicitNodeExecutable != null) {
+			return this.explicitNodeExecutable;
+		}
+		File npmExecutable = resolveNpmExecutable();
+		return NodeExecutableResolver.tryFindNextTo(npmExecutable)
+				.orElseThrow(() -> new IllegalStateException("Can't automatically determine node executable and none was specifically supplied!\n\n" + NodeExecutableResolver.explainMessage()));
 	}
 
 	public String resolveNpmrcContent() {

lib/src/main/java/com/diffplug/spotless/npm/NpmProcess.java

@@ -28,9 +28,12 @@ class NpmProcess {
 
 	private final File npmExecutable;
 
-	NpmProcess(File workingDir, File npmExecutable) {
+	private final File nodeExecutable;
+
+	NpmProcess(File workingDir, File npmExecutable, File nodeExecutable) {
 		this.workingDir = workingDir;
 		this.npmExecutable = npmExecutable;
+		this.nodeExecutable = nodeExecutable;
 	}
 
 	void install() {
@@ -61,11 +64,12 @@ private void npmAwait(String... args) {
 	private Process npm(String... args) {
 		List<String> processCommand = processCommand(args);
 		try {
-			return new ProcessBuilder()
+			ProcessBuilder processBuilder = new ProcessBuilder()
 					.inheritIO()
 					.directory(this.workingDir)
-					.command(processCommand)
-					.start();
+					.command(processCommand);
+			addEnvironmentVariables(processBuilder);
+			return processBuilder.start();
 		} catch (IOException e) {
 			throw new NpmProcessException("Failed to launch npm command '" + commandLine(args) + "'.", e);
 		}
@@ -78,6 +82,10 @@ private List<String> processCommand(String... args) {
 		return command;
 	}
 
+	private void addEnvironmentVariables(ProcessBuilder processBuilder) {
+		processBuilder.environment().put("PATH", this.nodeExecutable.getParentFile().getAbsolutePath() + File.pathSeparator + System.getenv("PATH"));
+	}
+
 	private String commandLine(String... args) {
 		return "npm " + Arrays.stream(args).collect(Collectors.joining(" "));
 	}

lib/src/main/java/com/diffplug/spotless/npm/PrettierFormatterStep.java

@@ -74,9 +74,11 @@ private static class State extends NpmFormatterStepStateBase implements Serializ
 									"/com/diffplug/spotless/npm/common-serve.js",
 									"/com/diffplug/spotless/npm/prettier-serve.js"),
 							npmPathResolver.resolveNpmrcContent()),
-					projectDir,
-					buildDir,
-					npmPathResolver.resolveNpmExecutable());
+					new NpmFormatterStepLocations(
+							projectDir,
+							buildDir,
+							npmPathResolver.resolveNpmExecutable(),
+							npmPathResolver.resolveNodeExecutable()));
 			this.prettierConfig = requireNonNull(prettierConfig);
 		}
 

lib/src/main/java/com/diffplug/spotless/npm/TsFmtFormatterStep.java

@@ -80,9 +80,11 @@ public State(String stepName, Map<String, String> versions, File projectDir, Fil
 									"/com/diffplug/spotless/npm/common-serve.js",
 									"/com/diffplug/spotless/npm/tsfmt-serve.js"),
 							npmPathResolver.resolveNpmrcContent()),
-					projectDir,
-					buildDir,
-					npmPathResolver.resolveNpmExecutable());
+					new NpmFormatterStepLocations(
+							projectDir,
+							buildDir,
+							npmPathResolver.resolveNpmExecutable(),
+							npmPathResolver.resolveNodeExecutable()));
 			this.buildDir = requireNonNull(buildDir);
 			this.configFile = configFile;
 			this.inlineTsFmtSettings = inlineTsFmtSettings == null ? new TreeMap<>() : new TreeMap<>(inlineTsFmtSettings);

plugin-gradle/CHANGES.md

@@ -4,6 +4,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 
 ## [Unreleased]
 ### Added
+* Allow to specify node executable for node-based formatters using `nodeExecutable` parameter ([#1500](https://github.com/diffplug/spotless/pull/1500))
 ### Fixed
 * The default list of type annotations used by `formatAnnotations` has had 8 more annotations from the Checker Framework added [#1494](https://github.com/diffplug/spotless/pull/1494)
 ### Changes

plugin-gradle/README.md

@@ -844,18 +844,23 @@ spotless {
 ### npm detection
 
 Prettier is based on NodeJS, so a working NodeJS installation (especially npm) is required on the host running spotless.
-Spotless will try to auto-discover an npm installation. If that is not working for you, it is possible to directly configure the npm binary to use.
+Spotless will try to auto-discover an npm installation. If that is not working for you, it is possible to directly configure the npm
+and/or node binary to use.
 
 ```gradle
 spotless {
   format 'javascript', {
-    prettier().npmExecutable('/usr/bin/npm').config(...)
+    prettier().npmExecutable('/usr/bin/npm').nodeExecutable('/usr/bin/node').config(...)
 ```
 
+If you provide both `npmExecutable` and `nodeExecutable`, spotless will use these paths. If you specify only one of the
+two, spotless will assume the other one is in the same directory.
+
 ### `.npmrc` detection
 
 Spotless picks up npm configuration stored in a `.npmrc` file either in the project directory or in your user home.
-Alternatively you can supply spotless with a location of the `.npmrc` file to use. (This can be combined with `npmExecutable`, of course.)
+Alternatively you can supply spotless with a location of the `.npmrc` file to use. (This can be combined with
+`npmExecutable` and `nodeExecutable`, of course.)
 
 ```gradle
 spotless {