Add config reader for user-defined difftools

see: http://git-scm.com/docs/git-difftool

* add config reader for user-defined difftools
  * diff.tool
  * diff.guitool
  * difftool.prompt
  * difftool.trustExitCode
  * difftool.<tool>.path
  * difftool.<tool>.cmd
* add pre-defined difftools
* implemented "git difftool --tool-help" to verify config reader and
pre-defined difftools

Bug: 356832
Change-Id: Idde8fddbef61f3378ee565c6321570b3962d0e1d
Signed-off-by: Andre Bossert <andre.bossert@siemens.com>
Signed-off-by: Simeon Andreev <simeon.danailov.andreev@gmail.com>

1 files changed, 56 insertions, 12 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/diffmergetool/ExternalDiffToolTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/diffmergetool/ExternalDiffToolTest.java
index f07d9d1afc..b141a86f76 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/diffmergetool/ExternalDiffToolTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/diffmergetool/ExternalDiffToolTest.java
@@ -9,9 +9,18 @@
  */
 package org.eclipse.jgit.internal.diffmergetool;
 
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_DIFFTOOL_SECTION;
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_CMD;
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_GUITOOL;
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_PATH;
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_PROMPT;
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_TRUST_EXIT_CODE;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 
 import java.util.Collections;
+import java.util.LinkedHashSet;
+import java.util.Map;
 import java.util.Set;
 
 import org.eclipse.jgit.lib.internal.BooleanTriState;
@@ -29,27 +38,64 @@ public class ExternalDiffToolTest extends ExternalToolTest {
 		Set<String> actualToolNames = manager.getToolNames();
 		Set<String> expectedToolNames = Collections.emptySet();
 		assertEquals("Incorrect set of external diff tool names",
-				expectedToolNames,
-				actualToolNames);
+				expectedToolNames, actualToolNames);
 	}
 
 	@Test
 	public void testAllTools() {
 		DiffTools manager = new DiffTools(db);
 		Set<String> actualToolNames = manager.getAvailableTools().keySet();
-		Set<String> expectedToolNames = Collections.emptySet();
-		assertEquals("Incorrect set of available external diff tools",
-				expectedToolNames,
+		Set<String> expectedToolNames = new LinkedHashSet<>();
+		CommandLineDiffTool[] defaultTools = CommandLineDiffTool.values();
+		for (CommandLineDiffTool defaultTool : defaultTools) {
+			String toolName = defaultTool.name();
+			expectedToolNames.add(toolName);
+		}
+		assertEquals("Incorrect set of external diff tools", expectedToolNames,
 				actualToolNames);
 	}
 
 	@Test
+	public void testOverridePredefinedToolPath() {
+		String toolName = CommandLineDiffTool.guiffy.name();
+		String customToolPath = "/usr/bin/echo";
+
+		FileBasedConfig config = db.getConfig();
+		config.setString(CONFIG_DIFFTOOL_SECTION, toolName, CONFIG_KEY_CMD,
+				"echo");
+		config.setString(CONFIG_DIFFTOOL_SECTION, toolName, CONFIG_KEY_PATH,
+				customToolPath);
+
+		DiffTools manager = new DiffTools(db);
+		Map<String, ExternalDiffTool> tools = manager.getUserDefinedTools();
+		ExternalDiffTool diffTool = tools.get(toolName);
+		assertNotNull("Expected tool \"" + toolName + "\" to be user defined",
+				diffTool);
+
+		String toolPath = diffTool.getPath();
+		assertEquals("Expected external diff tool to have an overriden path",
+				customToolPath, toolPath);
+	}
+
+	@Test
 	public void testUserDefinedTools() {
+		FileBasedConfig config = db.getConfig();
+		String customToolname = "customTool";
+		config.setString(CONFIG_DIFFTOOL_SECTION, customToolname,
+				CONFIG_KEY_CMD, "echo");
+		config.setString(CONFIG_DIFFTOOL_SECTION, customToolname,
+				CONFIG_KEY_PATH, "/usr/bin/echo");
+		config.setString(CONFIG_DIFFTOOL_SECTION, customToolname,
+				CONFIG_KEY_PROMPT, "--no-prompt");
+		config.setString(CONFIG_DIFFTOOL_SECTION, customToolname,
+				CONFIG_KEY_GUITOOL, "--no-gui");
+		config.setString(CONFIG_DIFFTOOL_SECTION, customToolname,
+				CONFIG_KEY_TRUST_EXIT_CODE, "--no-trust-exit-code");
 		DiffTools manager = new DiffTools(db);
 		Set<String> actualToolNames = manager.getUserDefinedTools().keySet();
-		Set<String> expectedToolNames = Collections.emptySet();
-		assertEquals("Incorrect set of user defined external diff tools",
-				expectedToolNames,
+		Set<String> expectedToolNames = new LinkedHashSet<>();
+		expectedToolNames.add(customToolname);
+		assertEquals("Incorrect set of external diff tools", expectedToolNames,
 				actualToolNames);
 	}
 
@@ -59,8 +105,7 @@ public class ExternalDiffToolTest extends ExternalToolTest {
 		Set<String> actualToolNames = manager.getNotAvailableTools().keySet();
 		Set<String> expectedToolNames = Collections.emptySet();
 		assertEquals("Incorrect set of not available external diff tools",
-				expectedToolNames,
-				actualToolNames);
+				expectedToolNames, actualToolNames);
 	}
 
 	@Test
@@ -80,8 +125,7 @@ public class ExternalDiffToolTest extends ExternalToolTest {
 		int compareResult = manager.compare(newPath, oldPath, newId, oldId,
 				toolName, prompt, gui, trustExitCode);
 		assertEquals("Incorrect compare result for external diff tool",
-				expectedCompareResult,
-				compareResult);
+				expectedCompareResult, compareResult);
 	}
 
 	@Test