Allow unquoted canonical repository names with query

bazelbuild · Sep 11, 2024 · cf90523 · cf90523
1 parent 1e481ab
commit cf90523
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Showing 3 changed files with 43 additions and 5 deletions.
diff --git a/site/en/query/language.md b/site/en/query/language.md
@@ -86,7 +86,9 @@ tokens:
   hyphen, underscore, colon, dollar sign, tilde, left square brace, right square
   brace). However, unquoted words may not start with a hyphen `-` or asterisk `*`
   even though relative [target names](/concepts/labels#target-names) may start
-  with those characters.
+  with those characters. As a special rule meant to simplify the handling of
+  labels referring to external repositories, unquoted words that start with
+  `@@` may contain `+` characters.
 
   Unquoted words also may not include the characters plus sign `+` or equals
   sign `=`, even though those characters are permitted in target names. When

diff --git a/src/main/java/com/google/devtools/build/lib/query2/engine/Lexer.java b/src/main/java/com/google/devtools/build/lib/query2/engine/Lexer.java
@@ -167,8 +167,10 @@ private TokenKind getTokenKindForWord(String word) {
     return kind == null ? TokenKind.WORD : kind;
   }
 
-  private String scanWord() {
+  private String scanWord(char firstChar) {
     int oldPos = pos - 1;
+    boolean startsWithDoubleAt =
+        firstChar == '@' && pos < input.length() && input.charAt(pos) == '@';
     while (pos < input.length()) {
       switch (input.charAt(pos)) {
         case 'a',
@@ -245,6 +247,17 @@ private String scanWord() {
                 '[',
                 ']' ->
             pos++;
+        case '+' -> {
+          if (startsWithDoubleAt) {
+            // Allow unquoted canonical labels such as
+            // @@rules_jvm_external++maven+maven//:bar, but still parse @foo+@bar as two separate
+            // labels (here @foo refers to the @foo//:foo target).
+            // If @@foo+bar is intended to mean @@foo + bar, it can be written as such with spaces.
+            pos++;
+          } else {
+            return bufferSlice(oldPos, pos);
+          }
+        }
         default -> {
           return bufferSlice(oldPos, pos);
         }
@@ -261,8 +274,8 @@ private String scanWord() {
    *
    * @return the word or keyword token.
    */
-  private Token wordOrKeyword() {
-    String word = scanWord();
+  private Token wordOrKeyword(char firstChar) {
+    String word = scanWord(firstChar);
     TokenKind kind = getTokenKindForWord(word);
     return kind == TokenKind.WORD ? new Token(word) : new Token(kind);
   }
@@ -284,7 +297,7 @@ private void tokenize() throws QuerySyntaxException {
           /* ignore */
         }
         case '\'', '\"' -> addToken(quotedWord(c));
-        default -> addToken(wordOrKeyword());
+        default -> addToken(wordOrKeyword(c));
       }
     }
 

diff --git a/src/test/java/com/google/devtools/build/lib/query2/engine/LexerTest.java b/src/test/java/com/google/devtools/build/lib/query2/engine/LexerTest.java
@@ -141,4 +141,27 @@ public void testOperatorWithUnquotedExprWithSpecialCharacters() throws QuerySynt
     assertThat(tokens[6].kind).isEqualTo(Lexer.TokenKind.WORD);
     assertThat(tokens[7].kind).isEqualTo(Lexer.TokenKind.RPAREN);
   }
+
+  @Test
+  public void testUnquotedCanonicalLabels() throws QuerySyntaxException {
+    Lexer.Token[] tokens =
+        scan("somepath(@foo+@bar+//baz+@@foo +bar,  @@rules_jvm_external++maven+maven//:bar)");
+    assertThat(asString(tokens))
+        .isEqualTo(
+            "somepath ( @foo + @bar + //baz + @@foo + bar , @@rules_jvm_external++maven+maven//:bar ) EOF");
+    assertThat(tokens[0].kind).isEqualTo(Lexer.TokenKind.WORD);
+    assertThat(tokens[1].kind).isEqualTo(Lexer.TokenKind.LPAREN);
+    assertThat(tokens[2].kind).isEqualTo(Lexer.TokenKind.WORD);
+    assertThat(tokens[3].kind).isEqualTo(Lexer.TokenKind.PLUS);
+    assertThat(tokens[4].kind).isEqualTo(Lexer.TokenKind.WORD);
+    assertThat(tokens[5].kind).isEqualTo(Lexer.TokenKind.PLUS);
+    assertThat(tokens[6].kind).isEqualTo(Lexer.TokenKind.WORD);
+    assertThat(tokens[7].kind).isEqualTo(Lexer.TokenKind.PLUS);
+    assertThat(tokens[8].kind).isEqualTo(Lexer.TokenKind.WORD);
+    assertThat(tokens[9].kind).isEqualTo(Lexer.TokenKind.PLUS);
+    assertThat(tokens[10].kind).isEqualTo(Lexer.TokenKind.WORD);
+    assertThat(tokens[11].kind).isEqualTo(Lexer.TokenKind.COMMA);
+    assertThat(tokens[12].kind).isEqualTo(Lexer.TokenKind.WORD);
+    assertThat(tokens[13].kind).isEqualTo(Lexer.TokenKind.RPAREN);
+  }
 }