java/groovy completion: load more class name variants when prefix is changed (IDEA-168079)

java/java-impl/src/com/intellij/codeInsight/completion/JavaNoVariantsDelegator.java

@@ -65,8 +65,8 @@ public class JavaNoVariantsDelegator extends CompletionContributor {
     result.runRemainingContributors(parameters, tracker);
     final boolean empty = tracker.containsOnlyPackages || suggestAllAnnotations(parameters);
 
-    if (!empty && parameters.getInvocationCount() == 0) {
-      result.restartCompletionWhenNothingMatches();
+    if (JavaCompletionContributor.isClassNamePossible(parameters) && !JavaCompletionContributor.mayStartClassName(result)) {
+      result.restartCompletionOnAnyPrefixChange();
     }
 
     if (empty) {
@@ -207,7 +207,7 @@ public class JavaNoVariantsDelegator extends CompletionContributor {
 
     public ResultTracker(CompletionResultSet result) {
       myResult = result;
-      betterMatcher = new BetterPrefixMatcher(result);
+      betterMatcher = new BetterPrefixMatcher.AutoRestarting(result);
     }
 
     @Override

java/java-tests/testSrc/com/intellij/codeInsight/completion/JavaAutoPopupTest.groovy

@@ -1805,4 +1805,32 @@ ita<caret>
     assert lookup
     assert myFixture.lookupElementStrings == ['itar']
   }
+
+  void "test expand class list when typing more or moving caret"() {
+    myFixture.addClass 'package foo; public class KimeFamilyRange {}'
+    myFixture.addClass 'package foo; public class FamiliesRangesMetaData {}'
+    myFixture.addClass 'public class KSomethingInCurrentPackage {}'
+    myFixture.configureByText 'a.java', 'class Foo { <caret> }'
+
+    type 'F'
+    assert !myFixture.lookupElementStrings.contains('KimeFamilyRange')
+
+    type 'aRa'
+    myFixture.assertPreferredCompletionItems 0, 'FamiliesRangesMetaData', 'KimeFamilyRange'
+
+    4.times {
+      edt { myFixture.performEditorAction(IdeActions.ACTION_EDITOR_MOVE_CARET_LEFT) }
+      joinCompletion()
+    }
+    assert !myFixture.lookupElementStrings.contains('KimeFamilyRange')
+
+    type 'K'
+
+    4.times {
+      edt { myFixture.performEditorAction(IdeActions.ACTION_EDITOR_MOVE_CARET_RIGHT) }
+      joinCompletion()
+    }
+
+    myFixture.assertPreferredCompletionItems 0, 'KimeFamilyRange'
+  }
 }

platform/lang-impl/src/com/intellij/codeInsight/completion/impl/BetterPrefixMatcher.java

@@ -39,32 +39,43 @@ public class BetterPrefixMatcher extends PrefixMatcher {
     myMinMatchingDegree = minMatchingDegree;
   }
 
-  public BetterPrefixMatcher(CompletionResultSet set) {
-    this(set.getPrefixMatcher(), Integer.MIN_VALUE);
-  }
-
   @NotNull
   public BetterPrefixMatcher improve(CompletionResult result) {
     int degree = RealPrefixMatchingWeigher.getBestMatchingDegree(result.getLookupElement(), result.getPrefixMatcher());
     if (degree <= myMinMatchingDegree) return this;
 
-    return new BetterPrefixMatcher(myOriginal, degree);
+    return createCopy(myOriginal, degree);
   }
-  
+
+  @NotNull
+  protected BetterPrefixMatcher createCopy(PrefixMatcher original, int degree) {
+    return new BetterPrefixMatcher(original, degree);
+  }
+
   @Override
   public boolean prefixMatches(@NotNull String name) {
-    if (myHumpMatcher != null) {
-      FList<TextRange> fragments = myHumpMatcher.matchingFragments(name);
-      if (fragments == null || !MinusculeMatcher.isStartMatch(fragments)) {
-        return false;
-      }
-      return myHumpMatcher.matchingDegree(name, fragments) >= myMinMatchingDegree;
-    }
+    return prefixMatchesEx(name) == MatchingOutcome.BETTER_MATCH;
+  }
 
-    if (!myOriginal.prefixMatches(name) || !myOriginal.isStartMatch(name)) {
-      return false;
-    }
-    return myOriginal.matchingDegree(name) >= myMinMatchingDegree;
+  protected MatchingOutcome prefixMatchesEx(String name) {
+    return myHumpMatcher != null ? matchOptimized(name, myHumpMatcher) : matchGeneric(name);
+  }
+
+  private MatchingOutcome matchGeneric(String name) {
+    if (!myOriginal.prefixMatches(name)) return MatchingOutcome.NON_MATCH;
+    if (!myOriginal.isStartMatch(name)) return MatchingOutcome.WORSE_MATCH;
+    return myOriginal.matchingDegree(name) >= myMinMatchingDegree ? MatchingOutcome.BETTER_MATCH : MatchingOutcome.WORSE_MATCH;
+  }
+
+  private MatchingOutcome matchOptimized(String name, CamelHumpMatcher matcher) {
+    FList<TextRange> fragments = matcher.matchingFragments(name);
+    if (fragments == null) return MatchingOutcome.NON_MATCH;
+    if (!MinusculeMatcher.isStartMatch(fragments)) return MatchingOutcome.WORSE_MATCH;
+    return matcher.matchingDegree(name, fragments) >= myMinMatchingDegree ? MatchingOutcome.BETTER_MATCH : MatchingOutcome.WORSE_MATCH;
+  }
+
+  protected enum MatchingOutcome {
+    NON_MATCH, WORSE_MATCH, BETTER_MATCH
   }
 
   @Override
@@ -80,6 +91,34 @@ public class BetterPrefixMatcher extends PrefixMatcher {
   @NotNull
   @Override
   public PrefixMatcher cloneWithPrefix(@NotNull String prefix) {
-    return new BetterPrefixMatcher(myOriginal.cloneWithPrefix(prefix), myMinMatchingDegree);
+    return createCopy(myOriginal.cloneWithPrefix(prefix), myMinMatchingDegree);
+  }
+
+  public static class AutoRestarting extends BetterPrefixMatcher {
+    private final CompletionResultSet myResult;
+
+    public AutoRestarting(@NotNull CompletionResultSet result) {
+      this(result, result.getPrefixMatcher(), Integer.MIN_VALUE);
+    }
+
+    private AutoRestarting(CompletionResultSet result, PrefixMatcher original, int minMatchingDegree) {
+      super(original, minMatchingDegree);
+      myResult = result;
+    }
+
+    @NotNull
+    @Override
+    protected BetterPrefixMatcher createCopy(PrefixMatcher original, int degree) {
+      return new AutoRestarting(myResult, original, degree);
+    }
+
+    @Override
+    protected MatchingOutcome prefixMatchesEx(String name) {
+      MatchingOutcome outcome = super.prefixMatchesEx(name);
+      if (outcome == MatchingOutcome.WORSE_MATCH) {
+        myResult.restartCompletionOnAnyPrefixChange();
+      }
+      return outcome;
+    }
   }
 }

plugins/groovy/src/org/jetbrains/plugins/groovy/lang/completion/GroovyNoVariantsDelegator.java

@@ -52,8 +52,8 @@ public class GroovyNoVariantsDelegator extends CompletionContributor {
     result.runRemainingContributors(parameters, tracker);
     final boolean empty = tracker.containsOnlyPackages || suggestAnnotations(parameters);
 
-    if (!empty && parameters.getInvocationCount() == 0) {
-      result.restartCompletionWhenNothingMatches();
+    if (GrMainCompletionProvider.isClassNamePossible(parameters.getPosition()) && !JavaCompletionContributor.mayStartClassName(result)) {
+      result.restartCompletionOnAnyPrefixChange();
     }
 
     if (empty) {

plugins/groovy/test/org/jetbrains/plugins/groovy/completion/GroovyAutoPopupTest.groovy

@@ -248,5 +248,33 @@ foo(new <caret>)
     assert !lookup
   }
 
+  void "test expand class list when typing more or moving caret"() {
+    myFixture.addClass 'package foo; public class KimeFamilyRange {}'
+    myFixture.addClass 'package foo; public class FamiliesRangesMetaData {}'
+    myFixture.addClass 'public class KSomethingInCurrentPackage {}'
+    myFixture.configureByText 'a.groovy', '<caret>'
+
+    type 'F'
+    assert !myFixture.lookupElementStrings.contains('KimeFamilyRange')
+
+    type 'aRa'
+    myFixture.assertPreferredCompletionItems 0, 'FamiliesRangesMetaData', 'KimeFamilyRange'
+
+    4.times {
+      edt { myFixture.performEditorAction(IdeActions.ACTION_EDITOR_MOVE_CARET_LEFT) }
+      myTester.joinCompletion()
+    }
+    assert !myFixture.lookupElementStrings.contains('KimeFamilyRange')
+
+    type 'K'
+
+    4.times {
+      edt { myFixture.performEditorAction(IdeActions.ACTION_EDITOR_MOVE_CARET_RIGHT) }
+      myTester.joinCompletion()
+    }
+
+    myFixture.assertPreferredCompletionItems 0, 'KimeFamilyRange'
+  }
+
 
 }