Fix handling of backslash-escaped CRLF line terminators.

The character sequences in the test cases behave the same way Python does.

Fixed #1306.

--
MOS_MIGRATED_REVID=125568600

1 files changed, 29 insertions, 6 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/syntax/Lexer.java b/src/main/java/com/google/devtools/build/lib/syntax/Lexer.java
index 1b10a667a6..1d60d50e82 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/Lexer.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/Lexer.java
@@ -349,13 +349,28 @@ public final class Lexer {
             // Insert \ and the following character.
             // As in Python, it means that a raw string can never end with a single \.
             literal.append('\\');
-            literal.append(buffer[pos]);
-            pos++;
+            if (pos + 1 < buffer.length && buffer[pos] == '\r' && buffer[pos + 1] == '\n') {
+              literal.append("\n");
+              pos += 2;
+            } else if (buffer[pos] == '\r' || buffer[pos] == '\n') {
+              literal.append("\n");
+              pos += 1;
+            } else {
+              literal.append(buffer[pos]);
+              pos += 1;
+            }
             break;
           }
           c = buffer[pos];
           pos++;
           switch (c) {
+            case '\r':
+              if (pos < buffer.length && buffer[pos] == '\n') {
+                pos += 1;
+                break;
+              } else {
+                break;
+              }
             case '\n':
               // ignore end of line character
               break;
@@ -460,9 +475,15 @@ public final class Lexer {
           return t;
         case '\\':
           if (isRaw) {
-            // skip the next character
-            pos++;
-            break;
+            if (pos + 1 < buffer.length && buffer[pos] == '\r' && buffer[pos + 1] == '\n') {
+              // There was a CRLF after the newline. No shortcut possible, since it needs to be
+              // transformed into a single LF.
+              pos = oldPos + 1;
+              return escapedStringLiteral(quot, true);
+            } else {
+              pos++;
+              break;
+            }
           }
           // oops, hit an escape, need to start over & build a new string buffer
           pos = oldPos + 1;
@@ -757,7 +778,9 @@ public final class Lexer {
       case '\\': {
         // Backslash character is valid only at the end of a line (or in a string)
         if (pos + 1 < buffer.length && buffer[pos] == '\n') {
-          pos++; // skip the end of line character
+          pos += 1;  // skip the end of line character
+        } else if (pos + 2 < buffer.length && buffer[pos] == '\r' && buffer[pos + 1] == '\n') {
+          pos += 2;  // skip the CRLF at the end of line
         } else {
           addToken(new Token(TokenKind.ILLEGAL, pos - 1, pos, Character.toString(c)));
         }