SQLite: Translate Math.Sign

Part of #18843

Author: bricelam

src/EFCore.Sqlite.Core/Query/Internal/SqliteMathTranslator.cs

@@ -42,11 +42,17 @@ public class SqliteMathTranslator : IMethodCallTranslator
         { typeof(Math).GetMethod(nameof(Math.Min), new[] { typeof(ushort), typeof(ushort) })!, "min" },
         { typeof(Math).GetMethod(nameof(Math.Round), new[] { typeof(double) })!, "round" },
         { typeof(Math).GetMethod(nameof(Math.Round), new[] { typeof(double), typeof(int) })!, "round" },
+        { typeof(Math).GetMethod(nameof(Math.Sign), new[] { typeof(double) })!, "sign" },
+        { typeof(Math).GetMethod(nameof(Math.Sign), new[] { typeof(float) })!, "sign" },
+        { typeof(Math).GetMethod(nameof(Math.Sign), new[] { typeof(long) })!, "sign" },
+        { typeof(Math).GetMethod(nameof(Math.Sign), new[] { typeof(sbyte) })!, "sign" },
+        { typeof(Math).GetMethod(nameof(Math.Sign), new[] { typeof(short) })!, "sign" },
         { typeof(MathF).GetMethod(nameof(MathF.Abs), new[] { typeof(float) })!, "abs" },
         { typeof(MathF).GetMethod(nameof(MathF.Max), new[] { typeof(float), typeof(float) })!, "max" },
         { typeof(MathF).GetMethod(nameof(MathF.Min), new[] { typeof(float), typeof(float) })!, "min" },
         { typeof(MathF).GetMethod(nameof(MathF.Round), new[] { typeof(float) })!, "round" },
-        { typeof(MathF).GetMethod(nameof(MathF.Round), new[] { typeof(float), typeof(int) })!, "round" }
+        { typeof(MathF).GetMethod(nameof(MathF.Round), new[] { typeof(float), typeof(int) })!, "round" },
+        { typeof(MathF).GetMethod(nameof(MathF.Sign), new[] { typeof(float) })!, "sign" }
     };
 
     private readonly ISqlExpressionFactory _sqlExpressionFactory;
@@ -78,7 +84,7 @@ public SqliteMathTranslator(ISqlExpressionFactory sqlExpressionFactory)
         {
             RelationalTypeMapping? typeMapping;
             List<SqlExpression>? newArguments = null;
-            if (sqlFunctionName == "max" || sqlFunctionName == "max")
+            if (sqlFunctionName == "max" || sqlFunctionName == "min")
             {
                 typeMapping = ExpressionExtensions.InferTypeMapping(arguments[0], arguments[1]);
                 newArguments = new List<SqlExpression>

test/EFCore.Sqlite.FunctionalTests/Query/NorthwindFunctionsQuerySqliteTest.cs

@@ -120,8 +120,17 @@ public override Task Sum_over_truncate_works_correctly_in_projection_2(bool asyn
     public override Task Where_math_round2(bool async)
         => AssertTranslationFailed(() => base.Where_math_round2(async));
 
-    public override Task Where_math_sign(bool async)
-        => AssertTranslationFailed(() => base.Where_math_sign(async));
+    public override async Task Where_math_sign(bool async)
+    {
+        await base.Where_math_sign(async);
+
+        AssertSql(
+"""
+SELECT "o"."OrderID", "o"."ProductID", "o"."Discount", "o"."Quantity", "o"."UnitPrice"
+FROM "Order Details" AS "o"
+WHERE "o"."OrderID" = 11077 AND sign("o"."Discount") > 0
+""");
+    }
 
     public override Task Where_math_sin(bool async)
         => AssertTranslationFailed(() => base.Where_math_sin(async));
@@ -174,8 +183,17 @@ public override Task Where_mathf_power(bool async)
     public override Task Where_mathf_square(bool async)
         => AssertTranslationFailed(() => base.Where_mathf_square(async));
 
-    public override Task Where_mathf_sign(bool async)
-        => AssertTranslationFailed(() => base.Where_mathf_sign(async));
+    public override async Task Where_mathf_sign(bool async)
+    {
+        await base.Where_mathf_sign(async);
+
+        AssertSql(
+"""
+SELECT "o"."OrderID", "o"."ProductID", "o"."Discount", "o"."Quantity", "o"."UnitPrice"
+FROM "Order Details" AS "o"
+WHERE "o"."OrderID" = 11077 AND sign("o"."Discount") > 0
+""");
+    }
 
     public override Task Where_mathf_sin(bool async)
         => AssertTranslationFailed(() => base.Where_mathf_sin(async));