Support windows line endings in string reflowing

cushon · cushon · commit afe8ac5fa5e0 · 2019-04-03T14:18:52.000-07:00
MOE_MIGRATED_REVID=241798204
diff --git a/core/src/main/java/com/google/googlejavaformat/java/StringWrapper.java b/core/src/main/java/com/google/googlejavaformat/java/StringWrapper.java
@@ -75,6 +75,7 @@ static String wrap(final int columnLimit, final String input) throws FormatterEx
     }
 
     JCTree.JCCompilationUnit unit = parse(input, /* allowStringFolding= */ false);
+    String separator = Newlines.guessLineSeparator(input);
 
     // Paths to string literals that extend past the column limit.
     List<TreePath> toFix = new ArrayList<>();
@@ -133,7 +134,7 @@ public Void visitLiteral(LiteralTree literalTree, Void aVoid) {
       ImmutableList<String> components = stringComponents(input, unit, flat);
       replacements.put(
           Range.closedOpen(getStartPosition(flat.get(0)), getEndPosition(unit, getLast(flat))),
-          reflow(columnLimit, startColumn, trailing, components, first.get()));
+          reflow(separator, columnLimit, startColumn, trailing, components, first.get()));
     }
     String result = applyReplacements(input, replacements);
 
@@ -207,7 +208,7 @@ static int hasEscapedWhitespaceAt(String input, int idx) {
   }
 
   static int hasEscapedNewlineAt(String input, int idx) {
-    return Stream.of("\\n\\r", "\\r", "\\n")
+    return Stream.of("\\r\\n", "\\r", "\\n")
         .mapToInt(x -> input.startsWith(x, idx) ? x.length() : -1)
         .filter(x -> x != -1)
         .findFirst()
@@ -217,13 +218,15 @@ static int hasEscapedNewlineAt(String input, int idx) {
   /**
    * Reflows the given source text, trying to split on word boundaries.
    *
+   * @param separator the line separator
    * @param columnLimit the number of columns to wrap at
    * @param startColumn the column position of the beginning of the original text
    * @param trailing extra space to leave after the last line
    * @param components the text to reflow
    * @param first0 true if the text includes the beginning of its enclosing concat chain, i.e. a
    */
   private static String reflow(
+      String separator,
       int columnLimit,
       int startColumn,
       int trailing,
@@ -263,7 +266,7 @@ private static String reflow(
     return lines.stream()
         .collect(
             joining(
-                "\"\n" + Strings.repeat(" ", startColumn + (first0 ? 4 : -2)) + "+ \"",
+                "\"" + separator + Strings.repeat(" ", startColumn + (first0 ? 4 : -2)) + "+ \"",
                 "\"",
                 "\""));
   }
diff --git a/core/src/test/java/com/google/googlejavaformat/java/StringWrapperIntegrationTest.java b/core/src/test/java/com/google/googlejavaformat/java/StringWrapperIntegrationTest.java
@@ -190,7 +190,7 @@ public static Collection<Object[]> parameters() {
           "class T {", //
           "  String s = \"\\n\\n\\none\\n\\nlong\\n\\nincredibly\\n\\nunbroken\\n\\nsentence\\n\\n"
               + "moving\\n\\nfrom\\n\\n topic\\n\\nto\\n\\n topic\\n\\nso\\n\\nthat\\n\\nno-one"
-              + "\\n\\nhad\\n\\na\\n\\nchance\\n\\nto\\n\\ninterrupt\\n\\n\\n\";",
+              + "\\n\\nhad\\n\\na\\n\\nchance\\n\\nto\\n\\ninterrupt\\n\\n\";",
           "}"
         },
         {
@@ -214,7 +214,7 @@ public static Collection<Object[]> parameters() {
           "          + \"a\\n\\n\"",
           "          + \"chance\\n\\n\"",
           "          + \"to\\n\\n\"",
-          "          + \"interrupt\\n\\n\\n\";",
+          "          + \"interrupt\\n\\n\";",
           "}",
         },
       },
@@ -374,6 +374,18 @@ public void test() throws Exception {
     assertThat(StringWrapper.wrap(40, new Formatter().formatSource(input))).isEqualTo(output);
   }
 
+  @Test
+  public void testCR() throws Exception {
+    assertThat(StringWrapper.wrap(40, new Formatter().formatSource(input.replace("\n", "\r"))))
+        .isEqualTo(output.replace("\n", "\r"));
+  }
+
+  @Test
+  public void testCRLF() throws Exception {
+    assertThat(StringWrapper.wrap(40, new Formatter().formatSource(input.replace("\n", "\r\n"))))
+        .isEqualTo(output.replace("\n", "\r\n"));
+  }
+
   @Test
   public void idempotent() throws Exception {
     String wrap = StringWrapper.wrap(40, new Formatter().formatSource(input));
