Score overloads to get best match

fibphp · Aug 3, 2018 · e553bdc · e553bdc
1 parent 0fff35f
commit e553bdc
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Showing 5 changed files with 83 additions and 9 deletions.
diff --git a/CLanguage/Interpreter/FunctionContext.cs b/CLanguage/Interpreter/FunctionContext.cs
@@ -71,12 +71,23 @@ public override ResolvedVariable ResolveVariable (string name, CType[] argTypes)
             //
             // Look for global functions
             //
+            BaseFunction ff = null;
+            var fi = -1;
+            var fs = 0;
             for (var i = 0; i < exe.Functions.Count; i++) {
                 var f = exe.Functions[i];
                 if (f.Name == name && string.IsNullOrEmpty (f.NameContext)) {
-                    return new ResolvedVariable (f, i);
+                    var score = f.FunctionType.ScoreParameterTypesMatches (argTypes);
+                    if (score > fs) {
+                        ff = f;
+                        fi = i;
+                        fs = score;
+                    }
                 }
             }
+            if (ff != null) {
+                return new ResolvedVariable (ff, fi);
+            }
 
             context.Report.Error (103, "The name '" + name + "' does not exist in the current context");
             return null;
@@ -88,6 +99,7 @@ public override ResolvedVariable ResolveMethodFunction (CStructType structType,
 
                 var nameContext = structType.Name;
 
+                var funcs = exe.Functions.Select ((f, i) => (f, i)).Where (x => x.Item1.NameContext == nameContext && x.Item1.Name == method.Name);
                 for (var i = 0; i < exe.Functions.Count; i++) {
                     var f = exe.Functions[i];
                     if (f.NameContext == nameContext && f.Name == method.Name && f.FunctionType.ParameterTypesEqual (ftype)) {

diff --git a/CLanguage/Syntax/FuncallExpression.cs b/CLanguage/Syntax/FuncallExpression.cs
@@ -99,7 +99,10 @@ Overload ResolveOverload (Expression function, CType[] argTypes, EmitContext ec)
                     else {
                         var methodq = from m in methods
                                       let mt = m.MemberType as CFunctionType
-                                      where mt != null && mt.ParameterTypesMatchArgs (argTypes)
+                                      where mt != null
+                                      let score = mt.ScoreParameterTypesMatches (argTypes)
+                                      where score > 0
+                                      orderby score descending
                                       select m;
                         var method = methodq.FirstOrDefault ();
                         if (method == null) {

diff --git a/CLanguage/Types/CFunctionType.cs b/CLanguage/Types/CFunctionType.cs
@@ -75,21 +75,30 @@ public override string ToString()
             return s;
         }
 
-        public bool ParameterTypesMatchArgs (CType[] argTypes)
+        public int ScoreParameterTypesMatches (CType[] argTypes)
         {
+            if (argTypes == null)
+                return 1;
+
             if (Parameters.Count != argTypes.Length)
-                return false;
+                return 0;
+
+            var score = 1;
 
             for (var i = 0; i < Parameters.Count; i++) {
                 var ft = argTypes[i];
                 var tt = Parameters[i].ParameterType;
 
-                if (!ft.CanCastTo (tt))
-                    return false;
+                if (ft.Equals (tt)) {
+                    score += 100;
+                }
+                else if (ft.CanCastTo (tt)) {
+                    score += 50;
+                }
             }
-
-            return true;
-        }
+
+            return score;
+        }
 
         public bool ParameterTypesEqual (CFunctionType otherType)
         {

diff --git a/CLanguageTests/ArduinoTestMachineInfo.cs b/CLanguageTests/ArduinoTestMachineInfo.cs
@@ -6,6 +6,7 @@
 using System.IO;
 using System.Collections.Generic;
 using System.Text;
+using System.Xml.Linq;
 
 namespace CLanguage.Tests
 {
@@ -51,6 +52,11 @@ struct SerialClass {
     void println(int value);
     void println(const char *value);
 };
+struct MemberTest {
+    int f(int testme);
+    int f(double testme);
+};
+struct MemberTest test;
 struct SerialClass Serial;
 ";
 
@@ -74,6 +80,8 @@ struct SerialClass Serial;
             AddInternalFunction ("void SerialClass::println (int value, int base)", Arduino.SerialPrintlnII);
             AddInternalFunction ("void SerialClass::println (int value)", Arduino.SerialPrintlnI);
             AddInternalFunction ("void SerialClass::println (const char *value)", Arduino.SerialPrintlnS);
+            AddInternalFunction ("int MemberTest::f (int)", x => x.Push (1));
+            AddInternalFunction ("int MemberTest::f (double)", x => x.Push (2));
 		}
 
 		static void AssertAreEqual (CInterpreter state)

diff --git a/CLanguageTests/OverloadTests.cs b/CLanguageTests/OverloadTests.cs
@@ -0,0 +1,42 @@
+using System;
+
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using CLanguage.Interpreter;
+
+namespace CLanguage.Tests
+{
+    [TestClass]
+    public class OverloadTests
+    {
+        CInterpreter Run (string code)
+        {
+            var fullCode = "void start() { __cinit(); main(); } " + code;
+            var i = CLanguageService.CreateInterpreter (fullCode, new ArduinoTestMachineInfo (), printer: new TestPrinter ());
+            i.Reset ("start");
+            i.Step ();
+            return i;
+        }
+
+        [TestMethod]
+        public void GlobalScoring ()
+        {
+            var i = Run (@"
+int f(int x) { return 1; }
+int f(double x) { return 2; }
+void main () {
+    assertAreEqual (1, f(0));
+    assertAreEqual (2, f(0.0));
+}");
+        }
+
+        [TestMethod]
+        public void MemberScoring ()
+        {
+            var i = Run (@"
+void main () {
+    assertAreEqual (1, test.f(0));
+    assertAreEqual (2, test.f(0.0));
+}");
+        }
+    }
+}