Replace tabs with spaces before merge: --expandtab

README.md

@@ -57,6 +57,11 @@ Usage: <main class> [options] [command] [command options]
           -r, --ruleset
              The ruleset to use when you merge poms. If you don't specify a ruleset,
              a default ruleset will be used. Default is ProjectAndParentVersionRule with our strategy.
+          -e, --expandtab
+             Replace all indentation tabs with the specified amount of spaces.
+             Note: this is just a subset of the git's -Xignore-all-space
+             functionality. Misalignment after the tab replacement will still result in the
+             merge conflicts.
 
     replace      Updates the parent version and/or the project version in the given pom.xml
       Usage: replace [options]

src/main/java/de/oppermann/pomutils/Main.java

@@ -93,6 +93,23 @@ protected static int mainInternal(String... args) {
 	}
 
 	private static int executePomMergeDriver(CommandPomMergeDriver mergeCommand) {
+		if (mergeCommand.getExpandTabSpaceCount() != null) {
+			int spaceCount = mergeCommand.getExpandTabSpaceCount().intValue();
+			if (mergeCommand.getOurPom() != null) {
+				TabExpander ourTabExpander = new TabExpander(mergeCommand.getOurPom(), spaceCount);
+				ourTabExpander.expand();
+			}
+
+			if (mergeCommand.getTheirPom() != null) {
+				TabExpander theirTabExpander = new TabExpander(mergeCommand.getTheirPom(), spaceCount);
+				theirTabExpander.expand();
+			}
+
+			if (mergeCommand.getBasePom() != null) {
+				TabExpander baseTabExpander = new TabExpander(mergeCommand.getBasePom(), spaceCount);
+				baseTabExpander.expand();
+			}
+		}
 		PomMergeDriver pomMergeDriver = new PomMergeDriver(mergeCommand.getRuleSet(), mergeCommand.getBasePom(),
 				mergeCommand.getOurPom(), mergeCommand.getTheirPom());
 		return pomMergeDriver.merge();

src/main/java/de/oppermann/pomutils/TabExpander.java

@@ -0,0 +1,148 @@
+package de.oppermann.pomutils;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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.
+ */
+
+import java.io.BufferedOutputStream;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.Arrays;
+
+import org.codehaus.plexus.util.IOUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Converts indentation-tabs to configurable amount of spaces.
+ * No support for Unicode-Spaces (other then standard 0x20 character).<br>
+ * <br>
+ * Example:
+ * <code><blockquote>
+ * \t\tString text = "\t";
+ * </blockquote></code>
+ *
+ * replacing tabs with 4 spaces get converted into
+ *
+ * <code><blockquote>
+ * ........String text = "\t";
+ * </blockquote></code>
+ * (`<code>.</code>´ represents a space character).<br>
+ * 
+ * @author Boris Brodski <brodsky_boris@yahoo.com>
+ *
+ */
+public class TabExpander {
+	private final Logger logger = LoggerFactory.getLogger(TabExpander.class);
+
+	private String filename;
+	private int spaceCount;
+
+	public TabExpander(String filename, int spaceCount) {
+		this.filename = filename;
+		this.spaceCount = spaceCount;
+	}
+
+	public void expand() {
+		logger.debug("Expanding indenting tabs into {} spaces [file={}]", spaceCount, filename);
+
+		byte[] fileInMemory = readFileIntoMemory();
+
+		boolean ok = false;
+		OutputStream outputStream = null;
+		try {
+			outputStream = new BufferedOutputStream(new FileOutputStream(filename));
+			copyExpandingTabs(fileInMemory, outputStream);
+
+			ok = true;
+		} catch (IOException e) {
+			throw new RuntimeException(e);
+		} finally {
+			if (outputStream != null) {
+				try {
+					outputStream.close();
+				} catch (IOException e) {
+					if (ok) {
+						throw new RuntimeException(e);
+					} else {
+						logger.error("Error closing output file " + filename, e);
+					}
+				}
+			}
+		}
+	}
+
+	private void copyExpandingTabs(byte[] fileInMemory, OutputStream outputStream) throws IOException {
+		byte[] indentSpaces = new byte[spaceCount];
+		Arrays.fill(indentSpaces, (byte)' ');
+		boolean inIndent = true;
+		for (int i = 0; i < fileInMemory.length; i++) {
+			switch (fileInMemory[i]) {
+			case '\n':
+			case '\r':
+				inIndent = true;
+				break;
+
+			case ' ':
+				break;
+
+			case '\t':
+				if (inIndent) {
+					outputStream.write(indentSpaces);
+					continue;
+				}
+				break;
+
+			default:
+				inIndent = false;
+			}
+
+			outputStream.write(fileInMemory[i]);
+		}
+	}
+
+	private byte[] readFileIntoMemory() {
+		InputStream inputStream = null;
+		byte[] fileInMemory;
+		boolean ok = false;
+		try {
+			inputStream = new FileInputStream(filename);
+			fileInMemory = IOUtil.toByteArray(inputStream);
+			ok = true;
+		} catch (IOException e) {
+			throw new RuntimeException(e);
+		} finally {
+			if (inputStream != null) {
+				try {
+					inputStream.close();
+				} catch (IOException e) {
+					if (ok) {
+						throw new RuntimeException(e);
+					} else {
+						logger.error("Error closing input file " + filename, e);
+					}
+				}
+			}
+		}
+		return fileInMemory;
+	}
+
+}

src/main/java/de/oppermann/pomutils/commands/CommandPomMergeDriver.java

@@ -51,6 +51,9 @@ public class CommandPomMergeDriver {
 	@Parameter(names = { "-r", "--ruleset" }, description = "The ruleset to use when you merge poms. If you don't specify a ruleset, a default ruleset will be used. Default is ProjectAndParentVersionRule with our strategy.")
 	private File ruleSetfile;
 
+	@Parameter(names = { "-e", "--expandtab" }, description = "Replace all indentation tabs with the specified amount of spaces.  Note: this is just a subset of the git's -Xignore-all-space functionality. Misalignment after the tab replacement will still result in the merge conflicts.", arity = 1)
+	private Integer expandTabSpaceCount;
+
 	public String getBasePom() {
 		return basePom;
 	}
@@ -78,4 +81,7 @@ public Ruleset getRuleSet() {
 		return new Ruleset(getRuleSetFile());
 	}
 
+	public Integer getExpandTabSpaceCount() {
+		return expandTabSpaceCount;
+	}
 }

src/test/java/de/oppermann/pomutils/TabExpanderTest.java

@@ -0,0 +1,106 @@
+package de.oppermann.pomutils;
+
+
+import java.io.File;
+
+import org.apache.commons.io.FileUtils;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import junit.framework.TestCase;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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.
+ */
+
+/**
+ * Tests tab expand feature:
+ *
+ * <pre>
+ * --expandtab={amount-of-space}
+ * </pre>
+ *
+ * @author Boris Brodski <brodsky_boris@yahoo.com>
+ *
+ */
+public class TabExpanderTest extends TestCase {
+	private static File dir;
+
+	public void setUp() {
+		dir = new File(TestUtils.resourceBaseTestFolder + "/" + "tabExpander");
+		dir.mkdirs();
+	}
+
+	public void testExpandTab1() throws Exception {
+		String result = expand("", 4);
+		assertEquals("", result);
+	}
+
+	public void testExpandTab2() throws Exception {
+		String result = expand("\t", 4);
+		assertEquals("    ", result);
+	}
+
+	public void testExpandTab3() throws Exception {
+		String result = expand("line1\n\t\tText:\ttest\n\t\t\n", 4);
+		assertEquals("line1\n        Text:\ttest\n        \n", result);
+	}
+
+	public void testExpandTab4() throws Exception {
+		String result = expand("line1\n\t\tText:\ttest\n\t\t\n", 1);
+		assertEquals("line1\n  Text:\ttest\n  \n", result);
+	}
+
+	public void testIntegrationWithoutExpandTab() throws Exception {
+		String myTestSubFolder = "tabExpander/withoutExpandTab";
+
+		TestUtils.prepareTestFolder(myTestSubFolder);
+
+		String[] args = {
+				"merge"
+				, "--our=" + TestUtils.resourceBaseTestFolder + "/" + myTestSubFolder + "/our.pom.xml"
+				, "--base=" + TestUtils.resourceBaseTestFolder + "/" + myTestSubFolder + "/base.pom.xml"
+				, "--their=" + TestUtils.resourceBaseTestFolder + "/" + myTestSubFolder + "/their.pom.xml" };
+
+		assertEquals(1, Main.mainInternal(args));
+	}
+
+	public void testIntegrationWithExpandTab() throws Exception {
+		String myTestSubFolder = "tabExpander/withExpandTab";
+
+		TestUtils.prepareTestFolder(myTestSubFolder);
+
+		String[] args = {
+				"merge"
+				, "--our=" + TestUtils.resourceBaseTestFolder + "/" + myTestSubFolder + "/our.pom.xml"
+				, "--base=" + TestUtils.resourceBaseTestFolder + "/" + myTestSubFolder + "/base.pom.xml"
+				, "--their=" + TestUtils.resourceBaseTestFolder + "/" + myTestSubFolder + "/their.pom.xml"
+				, "--expandtab=4" };
+
+		assertEquals(0, Main.mainInternal(args));
+	}
+
+	private String expand(String from, int spaces) throws Exception {
+		File file = new File(dir, "test.txt");
+		FileUtils.write(file, from);
+		new TabExpander(file.getAbsolutePath(), spaces).expand();
+
+		return FileUtils.readFileToString(file);
+	}
+
+}

src/test/resources/tabExpander/withExpandTab/base.pom.xml

@@ -0,0 +1,14 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>de.oppermann.pomutils</groupId>
+  <artifactId>pomutils</artifactId>
+	<version>base</version>
+  <dependencies>
+	<dependency>
+		<groupId>org.codehaus.mojo</groupId>
+        <artifactId>versions-maven-plugin</artifactId>
+		<version>2.1</version>
+        <type>maven-plugin</type>
+	</dependency>
+  </dependencies>
+</project>

src/test/resources/tabExpander/withExpandTab/our.pom.xml

@@ -0,0 +1,14 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>de.oppermann.pomutils</groupId>
+  <artifactId>pomutils</artifactId>
+    <version>our</version>
+  <dependencies>
+	<dependency>
+	    <groupId>org.codehaus.mojo</groupId>
+    	<artifactId>versions-maven-plugin</artifactId>
+		<version>2.5</version>
+	    <type>maven-plugin</type>
+    </dependency>
+  </dependencies>
+</project>

src/test/resources/tabExpander/withExpandTab/their.pom.xml

@@ -0,0 +1,14 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>de.oppermann.pomutils</groupId>
+  <artifactId>pomutils</artifactId>
+    <version>their</version>
+  <dependencies>
+	<dependency>
+		<groupId>org.codehaus.mojo</groupId>
+		<artifactId>versions-maven-plugin</artifactId>
+		<version>2.1</version>
+		<type>maven-plugin</type>
+	</dependency>
+  </dependencies>
+</project>

src/test/resources/tabExpander/withoutExpandTab/base.pom.xml

@@ -0,0 +1,14 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>de.oppermann.pomutils</groupId>
+  <artifactId>pomutils</artifactId>
+	<version>base</version>
+  <dependencies>
+	<dependency>
+		<groupId>org.codehaus.mojo</groupId>
+        <artifactId>versions-maven-plugin</artifactId>
+		<version>2.1</version>
+        <type>maven-plugin</type>
+	</dependency>
+  </dependencies>
+</project>

src/test/resources/tabExpander/withoutExpandTab/our.pom.xml

@@ -0,0 +1,14 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>de.oppermann.pomutils</groupId>
+  <artifactId>pomutils</artifactId>
+    <version>our</version>
+  <dependencies>
+	<dependency>
+	    <groupId>org.codehaus.mojo</groupId>
+    	<artifactId>versions-maven-plugin</artifactId>
+		<version>2.5</version>
+	    <type>maven-plugin</type>
+    </dependency>
+  </dependencies>
+</project>

src/test/resources/tabExpander/withoutExpandTab/their.pom.xml

@@ -0,0 +1,14 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>de.oppermann.pomutils</groupId>
+  <artifactId>pomutils</artifactId>
+    <version>their</version>
+  <dependencies>
+	<dependency>
+		<groupId>org.codehaus.mojo</groupId>
+		<artifactId>versions-maven-plugin</artifactId>
+		<version>2.1</version>
+		<type>maven-plugin</type>
+	</dependency>
+  </dependencies>
+</project>