Preserve the M ordinate in geometry SQL literals and JSON

src/EFCore.PG.NTS/Storage/Internal/NpgsqlGeometryTypeMapping.cs

@@ -91,7 +91,7 @@ protected override string GenerateNonNullSqlLiteral(object value)
         }
 
         builder
-            .Append(geometry.AsText())
+            .Append(new WKTWriter(4).Write(geometry))
             .Append('\'');
 
         return builder.ToString();

src/EFCore.PG.NTS/Storage/Internal/NpgsqlJsonGeometryWktReaderWriter.cs

@@ -30,7 +30,7 @@ public override Geometry FromJsonTyped(ref Utf8JsonReaderManager manager, object
     /// <inheritdoc />
     public override void ToJsonTyped(Utf8JsonWriter writer, Geometry value)
     {
-        var wkt = value.ToText();
+        var wkt = new WKTWriter(4).Write(value);
 
         // If the SRID is defined, prefix the WKT with it (SRID=4326;POINT(-44.3 60.1))
         // Although this is a PostgreSQL extension, NetTopologySuite supports it (see #3236)

test/EFCore.PG.FunctionalTests/JsonTypesNpgsqlTest.cs

@@ -488,7 +488,7 @@ public override async Task Can_read_write_point_with_M()
         await Can_read_and_write_JSON_value<PointMType, Point>(
             nameof(PointMType.PointM),
             factory.CreatePoint(new CoordinateM(2, 4, 6)),
-            """{"Prop":"SRID=4326;POINT (2 4)"}""");
+            """{"Prop":"SRID=4326;POINT M(2 4 6)"}""");
     }
 
     public override async Task Can_read_write_point_with_Z()
@@ -508,7 +508,7 @@ public override async Task Can_read_write_point_with_Z_and_M()
         await Can_read_and_write_JSON_value<PointZMType, Point>(
             nameof(PointZMType.PointZM),
             factory.CreatePoint(new CoordinateZM(1, 2, 3, 4)),
-            """{"Prop":"SRID=4326;POINT Z(1 2 3)"}""");
+            """{"Prop":"SRID=4326;POINT ZM(1 2 3 4)"}""");
     }
 
     public override async Task Can_read_write_line_string()

test/EFCore.PG.Tests/Storage/NpgsqlNetTopologySuiteTypeMappingTest.cs

@@ -0,0 +1,32 @@
+using NetTopologySuite.Geometries;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Storage.Internal;
+
+namespace Npgsql.EntityFrameworkCore.PostgreSQL.Storage;
+
+public class NpgsqlNetTopologySuiteTypeMappingTest
+{
+    [Fact]
+    public void GenerateSqlLiteral_returns_point_literal()
+        => Assert.Equal(
+            "GEOMETRY 'POINT (1 2)'",
+            new NpgsqlGeometryTypeMapping<Point>("geometry", isGeography: false).GenerateSqlLiteral(new Point(1, 2)));
+
+    [Fact]
+    public void GenerateSqlLiteral_returns_point_literal_with_Z()
+        => Assert.Equal(
+            "GEOMETRY 'POINT Z(1 2 3)'",
+            new NpgsqlGeometryTypeMapping<Point>("geometry", isGeography: false).GenerateSqlLiteral(new Point(new CoordinateZ(1, 2, 3))));
+
+    [Fact] // #4093
+    public void GenerateSqlLiteral_returns_point_literal_with_M()
+        => Assert.Equal(
+            "GEOMETRY 'POINT M(1 2 4)'",
+            new NpgsqlGeometryTypeMapping<Point>("geometry", isGeography: false).GenerateSqlLiteral(new Point(new CoordinateM(1, 2, 4))));
+
+    [Fact] // #4093
+    public void GenerateSqlLiteral_returns_point_literal_with_Z_and_M()
+        => Assert.Equal(
+            "GEOGRAPHY 'SRID=4326;POINT ZM(1 2 3 4)'",
+            new NpgsqlGeometryTypeMapping<Point>("geography", isGeography: true).GenerateSqlLiteral(
+                new Point(new CoordinateZM(1, 2, 3, 4)) { SRID = 4326 }));
+}