From d9f8050ad355b7d89bf3b7cb9065e3462e742a25 Mon Sep 17 00:00:00 2001
From: Roman Shevchenko <roman.shevchenko@jetbrains.com>
Date: Sun, 1 Aug 2010 22:04:25 +0400
Subject: [PATCH] New Java parser (completion hack)

---
 .../lang/java/parser/DeclarationParser.java   | 17 +++++++++++--
 .../declarations/CompletionHack2.txt          | 25 +++++++++++++++++++
 .../parser/partial/DeclarationParserTest.java |  1 +
 3 files changed, 41 insertions(+), 2 deletions(-)
 create mode 100644 java/java-tests/testData/psi/parser-partial/declarations/CompletionHack2.txt

diff --git a/java/java-impl/src/com/intellij/lang/java/parser/DeclarationParser.java b/java/java-impl/src/com/intellij/lang/java/parser/DeclarationParser.java
index c9e55e75cded..34f5ae8bda41 100644
--- a/java/java-impl/src/com/intellij/lang/java/parser/DeclarationParser.java
+++ b/java/java-impl/src/com/intellij/lang/java/parser/DeclarationParser.java
@@ -40,6 +40,8 @@ public class DeclarationParser {
   private static final TokenSet AFTER_END_DECLARATION_SET = TokenSet.create(JavaElementType.FIELD, JavaElementType.METHOD);
   private static final TokenSet BEFORE_LBRACE_ELEMENTS_SET = TokenSet.create(
     JavaTokenType.IDENTIFIER, JavaTokenType.COMMA, JavaTokenType.EXTENDS_KEYWORD, JavaTokenType.IMPLEMENTS_KEYWORD);
+  private static final TokenSet APPEND_TO_METHOD_SET = TokenSet.create(
+    JavaTokenType.IDENTIFIER, JavaTokenType.COMMA, JavaTokenType.THROWS_KEYWORD);
 
   private DeclarationParser() { }
 
@@ -411,8 +413,19 @@ public class DeclarationParser {
       StatementParser.parseCodeBlock(builder);
     }
     else {
-      error(builder, JavaErrorMessages.message("expected.lbrace.or.semicolon"));
-      // todo: special treatment - like in fields (DeclarationParserTest.testMultiLineUnclosed())
+      final PsiBuilder.Marker error = builder.mark();
+      // heuristic: going to next line obviously means method signature is over, starting new method (actually, another one completion hack)
+      final CharSequence text = builder.getOriginalText();
+      Loop:
+      while (true) {
+        for (int i = builder.getCurrentOffset() - 1; i >= 0; i--) {
+          final char ch = text.charAt(i);
+          if (ch == '\n') break Loop;
+          else if (ch != ' ' && ch != '\t') break;
+        }
+        if (!expect(builder, APPEND_TO_METHOD_SET)) break;
+      }
+      error.error(JavaErrorMessages.message("expected.lbrace.or.semicolon"));
     }
 
     declaration.done(anno ? JavaElementType.ANNOTATION_METHOD : JavaElementType.METHOD);
diff --git a/java/java-tests/testData/psi/parser-partial/declarations/CompletionHack2.txt b/java/java-tests/testData/psi/parser-partial/declarations/CompletionHack2.txt
new file mode 100644
index 000000000000..9c43b6b5b3df
--- /dev/null
+++ b/java/java-tests/testData/psi/parser-partial/declarations/CompletionHack2.txt
@@ -0,0 +1,25 @@
+PsiJavaFile:CompletionHack2.java
+  PsiJavaToken:LBRACE('{')
+  PsiWhiteSpace(' ')
+  PsiAnnotationMethod:foo
+    PsiModifierList:
+      <empty list>
+    PsiTypeParameterList
+      <empty list>
+    PsiTypeElement:String
+      PsiJavaCodeReferenceElement:String
+        PsiIdentifier:String('String')
+        PsiReferenceParameterList
+          <empty list>
+    PsiWhiteSpace(' ')
+    PsiIdentifier:foo('foo')
+    PsiParameterList:()
+      PsiJavaToken:LPARENTH('(')
+      PsiJavaToken:RPARENTH(')')
+    PsiReferenceList
+      <empty list>
+    PsiWhiteSpace(' ')
+    PsiErrorElement:'{' or ';' expected
+      PsiIdentifier:def('def')
+  PsiWhiteSpace(' ')
+  PsiJavaToken:RBRACE('}')
\ No newline at end of file
diff --git a/java/java-tests/testSrc/com/intellij/lang/java/parser/partial/DeclarationParserTest.java b/java/java-tests/testSrc/com/intellij/lang/java/parser/partial/DeclarationParserTest.java
index e72df739108f..8a51afbf9b6d 100644
--- a/java/java-tests/testSrc/com/intellij/lang/java/parser/partial/DeclarationParserTest.java
+++ b/java/java-tests/testSrc/com/intellij/lang/java/parser/partial/DeclarationParserTest.java
@@ -96,6 +96,7 @@ public class DeclarationParserTest extends JavaParsingTestCase {
   public void testErrors() { doParserTest("{ public static <error descr=\"2\">protected int f1 = 0; }", false, false); }
   public void testCompletionHack0() { doParserTest("{ <X IntelliJIdeaRulezz>\n String s = \"\"; }", false, false); }
   public void testCompletionHack1() { doParserTest("{ <X\n String s = \"\"; }", false, false); }
+  public void testCompletionHack2() { doParserTest("{ String foo() def }", true, false); }
   public void testWildcardParsing() { doParserTest("{ List<? extends B> x(Collection<? super B> x); }", false, false); }
   public void testParameterAnnotation() { doParserTest("{ void foo (@Annotation(value=77) int param) {} }", false, false); }
   public void testParameterizedMethod() { doParserTest("{ @Nullable <T> T bar() {} }", false, false); }