NPM formatters changed to have their signatures based on package.json file instead of the

whole node_modules directory.

Author: lutovich

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

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2020 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;
+
+class NodeServerLayout {
+
+	private final File nodeModulesDir;
+	private final File packageJsonFile;
+	private final File serveJsFile;
+
+	NodeServerLayout(File buildDir, String stepName) {
+		this.nodeModulesDir = new File(buildDir, "spotless-node-modules-" + stepName);
+		this.packageJsonFile = new File(nodeModulesDir, "package.json");
+		this.serveJsFile = new File(nodeModulesDir, "serve.js");
+	}
+
+	File nodeModulesDir() {
+		return nodeModulesDir;
+	}
+
+	File packageJsonFile() {
+		return packageJsonFile;
+	}
+
+	File serveJsFile() {
+		return serveJsFile;
+	}
+}

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

@@ -44,7 +44,7 @@ abstract class NpmFormatterStepStateBase implements Serializable {
 	private static final long serialVersionUID = 1460749955865959948L;
 
 	@SuppressWarnings("unused")
-	private final FileSignature nodeModulesSignature;
+	private final FileSignature packageJsonSignature;
 
 	@SuppressFBWarnings("SE_TRANSIENT_FIELD_NOT_RESTORED")
 	public final transient File nodeModulesDir;
@@ -56,22 +56,26 @@ abstract class NpmFormatterStepStateBase implements Serializable {
 
 	private final String stepName;
 
-	protected NpmFormatterStepStateBase(String stepName, NpmConfig npmConfig, File buildDir, @Nullable File npm) throws IOException {
+	protected NpmFormatterStepStateBase(String stepName, NpmConfig npmConfig, File buildDir,
+			@Nullable File npm) throws IOException {
 		this.stepName = requireNonNull(stepName);
 		this.npmConfig = requireNonNull(npmConfig);
 		this.npmExecutable = resolveNpm(npm);
 
-		this.nodeModulesDir = prepareNodeServer(buildDir);
-		this.nodeModulesSignature = FileSignature.signAsList(this.nodeModulesDir);
+		NodeServerLayout layout = prepareNodeServer(buildDir);
+		this.nodeModulesDir = layout.nodeModulesDir();
+		this.packageJsonSignature = FileSignature.signAsList(layout.packageJsonFile());
 	}
 
-	private File prepareNodeServer(File buildDir) throws IOException {
-		File targetDir = new File(buildDir, "spotless-node-modules-" + stepName);
-		NpmResourceHelper.assertDirectoryExists(targetDir);
-		NpmResourceHelper.writeUtf8StringToFile(targetDir, "package.json", this.npmConfig.getPackageJsonContent());
-		NpmResourceHelper.writeUtf8StringToFile(targetDir, "serve.js", this.npmConfig.getServeScriptContent());
-		runNpmInstall(targetDir);
-		return targetDir;
+	private NodeServerLayout prepareNodeServer(File buildDir) throws IOException {
+		NodeServerLayout layout = new NodeServerLayout(buildDir, stepName);
+		NpmResourceHelper.assertDirectoryExists(layout.nodeModulesDir());
+		NpmResourceHelper.writeUtf8StringToFile(layout.packageJsonFile(),
+				this.npmConfig.getPackageJsonContent());
+		NpmResourceHelper
+				.writeUtf8StringToFile(layout.serveJsFile(), this.npmConfig.getServeScriptContent());
+		runNpmInstall(layout.nodeModulesDir());
+		return layout;
 	}
 
 	private void runNpmInstall(File npmProjectDir) throws IOException {

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

@@ -28,9 +28,8 @@ private NpmResourceHelper() {
 		// no instance required
 	}
 
-	static void writeUtf8StringToFile(File targetDir, String fileName, String stringToWrite) throws IOException {
-		File packageJsonFile = new File(targetDir, fileName);
-		Files.write(packageJsonFile.toPath(), stringToWrite.getBytes(StandardCharsets.UTF_8));
+	static void writeUtf8StringToFile(File file, String stringToWrite) throws IOException {
+		Files.write(file.toPath(), stringToWrite.getBytes(StandardCharsets.UTF_8));
 	}
 
 	static void writeUtf8StringToOutputStream(String stringToWrite, OutputStream outputStream) throws IOException {