SE: Fix constant number pattern logic (#7931)

SonarSource · Aug 31, 2023 · 28f2de5 · 28f2de5
1 parent dc72d9e
commit 28f2de5
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Showing 2 changed files with 13 additions and 5 deletions.
diff --git a/analyzers/src/SonarAnalyzer.Common/SymbolicExecution/Roslyn/OperationProcessors/IsPattern.cs b/analyzers/src/SonarAnalyzer.Common/SymbolicExecution/Roslyn/OperationProcessors/IsPattern.cs
@@ -121,7 +121,14 @@ private static BoolConstraint BoolConstraintFromConstant(ProgramState state, IIs
             else if (state.Constraint<NumberConstraint>(constantPattern) is { } constantNumberConstraint
                 && value.Constraint<NumberConstraint>() is { } valueNumberConstraint)
             {
-                return BoolConstraint.From(valueNumberConstraint.Overlaps(constantNumberConstraint));
+                if (constantNumberConstraint.IsSingleValue && valueNumberConstraint.IsSingleValue)
+                {
+                    return BoolConstraint.From(constantNumberConstraint.Min == valueNumberConstraint.Min);
+                }
+                else if (!valueNumberConstraint.Overlaps(constantNumberConstraint))
+                {
+                    return BoolConstraint.False;
+                }
             }
         }
         return null; // We cannot take conclusive decision

diff --git a/...Analyzer.UnitTest/SymbolicExecution/Roslyn/RoslynSymbolicExecutionTest.PatternMatching.cs b/...Analyzer.UnitTest/SymbolicExecution/Roslyn/RoslynSymbolicExecutionTest.PatternMatching.cs
@@ -328,11 +328,11 @@ public void DeclarationPattern_Var_Deconstruction_DoesNotSetConstraint()
     [DataTestMethod]
     [DataRow("i == 42", 42, true)]
     [DataRow("i == 16", 42, false)]
-    [DataRow("i >= 42", 42, true)]
-    [DataRow("i <= 42", 42, true)]
+    [DataRow("i >= 42", 42, null)]
+    [DataRow("i <= 42", 42, null)]
     [DataRow("i >  42", 42, false)]
     [DataRow("i <  42", 42, false)]
-    public void ConstantNumberPatternSetBoolConstraint(string rangeCondition, int constant, bool expectedBoolConstraint)
+    public void ConstantNumberPatternSetBoolConstraint(string rangeCondition, int constant, bool? expectedBoolConstraint)
     {
         var code = $$"""
             if ({{rangeCondition}})
@@ -341,7 +341,8 @@ public void ConstantNumberPatternSetBoolConstraint(string rangeCondition, int co
                 Tag("Result", result);
             }
             """;
-        SETestContext.CreateCS(code, "int i").Validator.TagValue("Result").Should().HaveOnlyConstraints(BoolConstraint.From(expectedBoolConstraint), ObjectConstraint.NotNull);
+        var expected = expectedBoolConstraint == null ? null : BoolConstraint.From(expectedBoolConstraint.Value);
+        SETestContext.CreateCS(code, "int i").Validator.TagValue("Result").Should().HaveOnlyConstraints(expected, ObjectConstraint.NotNull);
     }
 
     [DataTestMethod]