Config: Handle leading/trailing single whitespaces

Change-Id: I468106acd2006d0a174c76dfd4bce231f1c7a6f8

org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/ConfigTest.java

@@ -965,4 +965,56 @@ public class ConfigTest {
 		expectedEx.expect(IllegalArgumentException.class);
 		parseTime("-1", MILLISECONDS);
 	}
+
+	@Test
+	public void testEscapeSpacesOnly() throws ConfigInvalidException {
+		assertEquals("", Config.escapeValue(""));
+		assertEquals("\" \"", Config.escapeValue(" "));
+		assertEquals("\"  \"", Config.escapeValue("  "));
+
+		assertParseRoundTrip(" ");
+		assertParseRoundTrip("  ");
+	}
+
+	@Test
+	public void testEscapeLeadingSpace() throws ConfigInvalidException {
+		assertEquals("x", Config.escapeValue("x"));
+		assertEquals("\" x\"", Config.escapeValue(" x"));
+		assertEquals("\"  x\"", Config.escapeValue("  x"));
+
+		assertParseRoundTrip("x");
+		assertParseRoundTrip(" x");
+		assertParseRoundTrip("  x");
+	}
+
+	@Test
+	public void testEscapeTrailingSpace() throws ConfigInvalidException {
+		assertEquals("x", Config.escapeValue("x"));
+		assertEquals("\"x  \"", Config.escapeValue("x  "));
+		assertEquals("x\" \"", Config.escapeValue("x "));
+
+		assertParseRoundTrip("x");
+		assertParseRoundTrip("x ");
+		assertParseRoundTrip("x  ");
+	}
+
+	@Test
+	public void testEscapeLeadingAndTrailingSpace()
+			throws ConfigInvalidException {
+		assertEquals("\" x \"", Config.escapeValue(" x "));
+		assertEquals("\"  x \"", Config.escapeValue("  x "));
+		assertEquals("\" x  \"", Config.escapeValue(" x  "));
+		assertEquals("\"  x  \"", Config.escapeValue("  x  "));
+
+		assertParseRoundTrip(" x ");
+		assertParseRoundTrip(" x  ");
+		assertParseRoundTrip("  x ");
+		assertParseRoundTrip("  x  ");
+	}
+
+	private static void assertParseRoundTrip(String value)
+			throws ConfigInvalidException {
+		Config c = parse("[foo]\nbar = " + Config.escapeValue(value));
+		assertEquals(value, c.getString("foo", null, "bar"));
+	}
 }

org.eclipse.jgit/src/org/eclipse/jgit/lib/Config.java

@@ -147,7 +147,10 @@ public class Config {
 	 *            the value to escape
 	 * @return the escaped value
 	 */
-	private static String escapeValue(final String x) {
+	static String escapeValue(final String x) {
+		if (x.isEmpty()) {
+			return ""; //$NON-NLS-1$
+		}
 		boolean inquote = false;
 		int lineStart = 0;
 		final StringBuilder r = new StringBuilder(x.length());
@@ -189,8 +192,7 @@ public class Config {
 				break;
 
 			case ' ':
-				if (!inquote && r.length() > 0
-						&& r.charAt(r.length() - 1) == ' ') {
+				if (!inquote && (r.length() == 0 || r.charAt(r.length() - 1) == ' ')) {
 					r.insert(lineStart, '"');
 					inquote = true;
 				}
@@ -202,6 +204,20 @@ public class Config {
 				break;
 			}
 		}
+
+		if (!inquote) {
+			// Ensure any trailing whitespace is quoted.
+			int s = x.length();
+			while (s > 0 && x.charAt(s - 1) == ' ') {
+				s--;
+			}
+			if (s != x.length()) {
+				// Can't insert at lineStart since there may be intervening quotes.
+				r.insert(s, '"');
+				inquote = true;
+			}
+		}
+
 		if (inquote) {
 			r.append('"');
 		}