# HG changeset patch
# User vromero
# Date 1506963862 25200
# Node ID 2e947e1bd907ec98e7cb829f2a673256a1cec0c8
# Parent  a0116bcc65b70dcb5824bebc28034cb2cfe607de
8187978: javac can show overload error messages that include non-valid candidates
Reviewed-by: mcimadamore
Contributed-by: bsrbnd@gmail.com

diff -r a0116bcc65b7 -r 2e947e1bd907 src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Resolve.java
--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Resolve.java	Mon Oct 02 12:29:44 2017 +0100
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Resolve.java	Mon Oct 02 10:04:22 2017 -0700
@@ -59,6 +59,7 @@
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
+import java.util.LinkedList;
 import java.util.Map;
 import java.util.Set;
 import java.util.function.BiFunction;
@@ -4040,14 +4041,35 @@
         }
         //where
             private Map<Symbol, JCDiagnostic> mapCandidates() {
-                Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<>();
+                MostSpecificMap candidates = new MostSpecificMap();
                 for (Candidate c : resolveContext.candidates) {
                     if (c.isApplicable()) continue;
-                    candidates.put(c.sym, c.details);
+                    candidates.put(c);
                 }
                 return candidates;
             }
 
+            @SuppressWarnings("serial")
+            private class MostSpecificMap extends LinkedHashMap<Symbol, JCDiagnostic> {
+                private void put(Candidate c) {
+                    ListBuffer<Symbol> overridden = new ListBuffer<>();
+                    for (Symbol s : keySet()) {
+                        if (s == c.sym) {
+                            continue;
+                        }
+                        if (c.sym.overrides(s, (TypeSymbol)s.owner, types, false)) {
+                            overridden.add(s);
+                        } else if (s.overrides(c.sym, (TypeSymbol)c.sym.owner, types, false)) {
+                            return;
+                        }
+                    }
+                    for (Symbol s : overridden) {
+                        remove(s);
+                    }
+                    put(c.sym, c.details);
+                }
+            }
+
             Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) {
                 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<>();
                 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
diff -r a0116bcc65b7 -r 2e947e1bd907 test/langtools/tools/javac/T8187978/FilterOutCandidatesForDiagnosticsTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/langtools/tools/javac/T8187978/FilterOutCandidatesForDiagnosticsTest.java	Mon Oct 02 10:04:22 2017 -0700
@@ -0,0 +1,18 @@
+/*
+ * @test  /nodynamiccopyright/
+ * @bug 8187978
+ * @summary javac can show overload error messages that include non-valid candidates
+ * @compile/fail/ref=FilterOutCandidatesForDiagnosticsTest.out -XDrawDiagnostics FilterOutCandidatesForDiagnosticsTest.java
+ */
+
+import java.util.*;
+
+class FilterOutCandidatesForDiagnosticsTest {
+    void test() {
+        make(new ArrayList<String>(), new ArrayList<Integer>()).add("");
+    }
+
+    <Z> Z make(Z z1, Z z2) {
+        return null;
+    }
+}
diff -r a0116bcc65b7 -r 2e947e1bd907 test/langtools/tools/javac/T8187978/FilterOutCandidatesForDiagnosticsTest.out
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/langtools/tools/javac/T8187978/FilterOutCandidatesForDiagnosticsTest.out	Mon Oct 02 10:04:22 2017 -0700
@@ -0,0 +1,2 @@
+FilterOutCandidatesForDiagnosticsTest.java:12:64: compiler.err.cant.apply.symbols: kindname.method, add, java.lang.String,{(compiler.misc.inapplicable.method: kindname.method, java.util.ArrayList, add(compiler.misc.type.captureof: 1, ? extends java.lang.Object&java.io.Serializable&java.lang.Comparable<? extends java.lang.Object&java.io.Serializable&java.lang.Comparable<?>>,java.lang.Object[],int), (compiler.misc.arg.length.mismatch)),(compiler.misc.inapplicable.method: kindname.method, java.util.ArrayList, add(compiler.misc.type.captureof: 1, ? extends java.lang.Object&java.io.Serializable&java.lang.Comparable<? extends java.lang.Object&java.io.Serializable&java.lang.Comparable<?>>), (compiler.misc.no.conforming.assignment.exists: (compiler.misc.inconvertible.types: java.lang.String, compiler.misc.type.captureof: 1, ? extends java.lang.Object&java.io.Serializable&java.lang.Comparable<? extends java.lang.Object&java.io.Serializable&java.lang.Comparable<?>>))),(compiler.misc.inapplicable.method: kindname.method, java.util.ArrayList, add(int,compiler.misc.type.captureof: 1, ? extends java.lang.Object&java.io.Serializable&java.lang.Comparable<? extends java.lang.Object&java.io.Serializable&java.lang.Comparable<?>>), (compiler.misc.arg.length.mismatch))}
+1 error
diff -r a0116bcc65b7 -r 2e947e1bd907 test/langtools/tools/javac/capture/Martin.out
--- a/test/langtools/tools/javac/capture/Martin.out	Mon Oct 02 12:29:44 2017 +0100
+++ b/test/langtools/tools/javac/capture/Martin.out	Mon Oct 02 10:04:22 2017 -0700
@@ -1,2 +1,2 @@
-Martin.java:15:11: compiler.err.cant.apply.symbols: kindname.method, addAll, java.util.List<compiler.misc.type.captureof: 1, ?>,{(compiler.misc.inapplicable.method: kindname.method, java.util.Collection, addAll(java.util.Collection<? extends compiler.misc.type.captureof: 2, ?>), (compiler.misc.no.conforming.assignment.exists: (compiler.misc.inconvertible.types: java.util.List<compiler.misc.type.captureof: 1, ?>, java.util.Collection<? extends compiler.misc.type.captureof: 2, ?>))),(compiler.misc.inapplicable.method: kindname.method, java.util.List, addAll(java.util.Collection<? extends compiler.misc.type.captureof: 2, ?>), (compiler.misc.no.conforming.assignment.exists: (compiler.misc.inconvertible.types: java.util.List<compiler.misc.type.captureof: 1, ?>, java.util.Collection<? extends compiler.misc.type.captureof: 2, ?>))),(compiler.misc.inapplicable.method: kindname.method, java.util.List, addAll(int,java.util.Collection<? extends compiler.misc.type.captureof: 2, ?>), (compiler.misc.arg.length.mismatch))}
+Martin.java:15:11: compiler.err.cant.apply.symbols: kindname.method, addAll, java.util.List<compiler.misc.type.captureof: 1, ?>,{(compiler.misc.inapplicable.method: kindname.method, java.util.List, addAll(java.util.Collection<? extends compiler.misc.type.captureof: 2, ?>), (compiler.misc.no.conforming.assignment.exists: (compiler.misc.inconvertible.types: java.util.List<compiler.misc.type.captureof: 1, ?>, java.util.Collection<? extends compiler.misc.type.captureof: 2, ?>))),(compiler.misc.inapplicable.method: kindname.method, java.util.List, addAll(int,java.util.Collection<? extends compiler.misc.type.captureof: 2, ?>), (compiler.misc.arg.length.mismatch))}
 1 error
diff -r a0116bcc65b7 -r 2e947e1bd907 test/langtools/tools/javac/lambda/8019480/T8019480.out
--- a/test/langtools/tools/javac/lambda/8019480/T8019480.out	Mon Oct 02 12:29:44 2017 +0100
+++ b/test/langtools/tools/javac/lambda/8019480/T8019480.out	Mon Oct 02 10:04:22 2017 -0700
@@ -1,3 +1,3 @@
-T8019480.java:21:34: compiler.err.cant.apply.symbols: kindname.method, add, java.lang.Object,{(compiler.misc.inapplicable.method: kindname.method, java.util.Collection, add(U), (compiler.misc.no.conforming.assignment.exists: (compiler.misc.inconvertible.types: java.lang.Object, U))),(compiler.misc.inapplicable.method: kindname.method, java.util.List, add(U), (compiler.misc.no.conforming.assignment.exists: (compiler.misc.inconvertible.types: java.lang.Object, U))),(compiler.misc.inapplicable.method: kindname.method, java.util.List, add(int,U), (compiler.misc.arg.length.mismatch))}
+T8019480.java:21:34: compiler.err.cant.apply.symbols: kindname.method, add, java.lang.Object,{(compiler.misc.inapplicable.method: kindname.method, java.util.List, add(U), (compiler.misc.no.conforming.assignment.exists: (compiler.misc.inconvertible.types: java.lang.Object, U))),(compiler.misc.inapplicable.method: kindname.method, java.util.List, add(int,U), (compiler.misc.arg.length.mismatch))}
 T8019480.java:21:46: compiler.err.report.access: clone(), protected, java.lang.Object
 2 errors