Fix migration history table lookup

src/EFCore.PG/Migrations/Internal/NpgsqlHistoryRepository.cs

@@ -31,26 +31,17 @@ protected override string ExistsSql
     {
         get
         {
-            var builder = new StringBuilder();
-
-            builder.Append("SELECT EXISTS (SELECT 1 FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n ON n.oid=c.relnamespace WHERE ");
-
             var stringTypeMapping = Dependencies.TypeMappingSource.GetMapping(typeof(string));
 
-            if (TableSchema is not null)
-            {
-                builder
-                    .Append("n.nspname=")
-                    .Append(stringTypeMapping.GenerateSqlLiteral(TableSchema))
-                    .Append(" AND ");
-            }
-
-            builder
-                .Append("c.relname=")
-                .Append(stringTypeMapping.GenerateSqlLiteral(TableName))
-                .Append(");");
-
-            return builder.ToString();
+            return
+$"""
+SELECT EXISTS (
+    SELECT 1 FROM pg_catalog.pg_class c
+    JOIN pg_catalog.pg_namespace n ON n.oid=c.relnamespace
+    WHERE n.nspname={stringTypeMapping.GenerateSqlLiteral(TableSchema ?? "public")} AND
+          c.relname={stringTypeMapping.GenerateSqlLiteral(TableName)}
+)
+""";
         }
     }
 

test/EFCore.PG.Tests/Migrations/NpgsqlHistoryRepositoryTest.cs

@@ -0,0 +1,189 @@
+using Npgsql.EntityFrameworkCore.PostgreSQL.TestUtilities;
+
+namespace Npgsql.EntityFrameworkCore.PostgreSQL.Migrations;
+
+public class NpgsqlHistoryRepositoryTest
+{
+    [ConditionalFact]
+    public void GetCreateScript_works()
+    {
+        var sql = CreateHistoryRepository().GetCreateScript();
+
+        Assert.Equal(
+"""
+CREATE TABLE "__EFMigrationsHistory" (
+    "MigrationId" character varying(150) NOT NULL,
+    "ProductVersion" character varying(32) NOT NULL,
+    CONSTRAINT "PK___EFMigrationsHistory" PRIMARY KEY ("MigrationId")
+);
+
+""", sql, ignoreLineEndingDifferences: true);
+    }
+
+    [ConditionalFact]
+    public void GetCreateScript_works_with_schema()
+    {
+        var sql = CreateHistoryRepository("my").GetCreateScript();
+
+        Assert.Equal(
+"""
+DO $EF$
+BEGIN
+    IF NOT EXISTS(SELECT 1 FROM pg_namespace WHERE nspname = 'my') THEN
+        CREATE SCHEMA my;
+    END IF;
+END $EF$;
+CREATE TABLE my."__EFMigrationsHistory" (
+    "MigrationId" character varying(150) NOT NULL,
+    "ProductVersion" character varying(32) NOT NULL,
+    CONSTRAINT "PK___EFMigrationsHistory" PRIMARY KEY ("MigrationId")
+);
+
+""", sql, ignoreLineEndingDifferences: true);
+    }
+
+    [ConditionalFact]
+    public void GetCreateIfNotExistsScript_works()
+    {
+        var sql = CreateHistoryRepository().GetCreateIfNotExistsScript();
+
+        Assert.Equal(
+"""
+CREATE TABLE IF NOT EXISTS "__EFMigrationsHistory" (
+    "MigrationId" character varying(150) NOT NULL,
+    "ProductVersion" character varying(32) NOT NULL,
+    CONSTRAINT "PK___EFMigrationsHistory" PRIMARY KEY ("MigrationId")
+);
+
+""", sql, ignoreLineEndingDifferences: true);
+    }
+
+    [ConditionalFact]
+    public void GetCreateIfNotExistsScript_works_with_schema()
+    {
+        var sql = CreateHistoryRepository("my").GetCreateIfNotExistsScript();
+
+        Assert.Equal(
+"""
+DO $EF$
+BEGIN
+    IF NOT EXISTS(SELECT 1 FROM pg_namespace WHERE nspname = 'my') THEN
+        CREATE SCHEMA my;
+    END IF;
+END $EF$;
+CREATE TABLE IF NOT EXISTS my."__EFMigrationsHistory" (
+    "MigrationId" character varying(150) NOT NULL,
+    "ProductVersion" character varying(32) NOT NULL,
+    CONSTRAINT "PK___EFMigrationsHistory" PRIMARY KEY ("MigrationId")
+);
+
+""", sql, ignoreLineEndingDifferences: true);
+    }
+
+    [ConditionalFact]
+    public void GetDeleteScript_works()
+    {
+        var sql = CreateHistoryRepository().GetDeleteScript("Migration1");
+
+        Assert.Equal(
+"""
+DELETE FROM "__EFMigrationsHistory"
+WHERE "MigrationId" = 'Migration1';
+
+""", sql, ignoreLineEndingDifferences: true);
+    }
+
+    [ConditionalFact]
+    public void GetInsertScript_works()
+    {
+        var sql = CreateHistoryRepository().GetInsertScript(
+            new HistoryRow("Migration1", "7.0.0"));
+
+        Assert.Equal(
+"""
+INSERT INTO "__EFMigrationsHistory" ("MigrationId", "ProductVersion")
+VALUES ('Migration1', '7.0.0');
+
+""", sql, ignoreLineEndingDifferences: true);
+    }
+
+    [ConditionalFact]
+    public void GetBeginIfNotExistsScript_works()
+    {
+        var sql = CreateHistoryRepository().GetBeginIfNotExistsScript("Migration1");
+
+        Assert.Equal(
+"""
+
+DO $EF$
+BEGIN
+    IF NOT EXISTS(SELECT 1 FROM "__EFMigrationsHistory" WHERE "MigrationId" = 'Migration1') THEN
+""", sql, ignoreLineEndingDifferences: true);
+    }
+
+    [ConditionalFact]
+    public void GetBeginIfExistsScript_works()
+    {
+        var sql = CreateHistoryRepository().GetBeginIfExistsScript("Migration1");
+
+        Assert.Equal(
+"""
+
+DO $EF$
+BEGIN
+    IF EXISTS(SELECT 1 FROM "__EFMigrationsHistory" WHERE "MigrationId" = 'Migration1') THEN
+""", sql, ignoreLineEndingDifferences: true);
+    }
+
+    [ConditionalFact]
+    public void GetEndIfScript_works()
+    {
+        var sql = CreateHistoryRepository().GetEndIfScript();
+
+        Assert.Equal(
+"""
+    END IF;
+END $EF$;
+""", sql, ignoreLineEndingDifferences: true);
+    }
+
+    private static IHistoryRepository CreateHistoryRepository(string schema = null)
+        => new TestDbContext(
+                new DbContextOptionsBuilder()
+                    .UseInternalServiceProvider(NpgsqlTestHelpers.Instance.CreateServiceProvider())
+                    .UseNpgsql(
+                        new NpgsqlConnection("Host=localhost;Database=DummyDatabase"),
+                        b => b.MigrationsHistoryTable(HistoryRepository.DefaultTableName, schema))
+                    .Options)
+            .GetService<IHistoryRepository>();
+
+    private class TestDbContext : DbContext
+    {
+        public TestDbContext(DbContextOptions options)
+            : base(options)
+        {
+        }
+
+        public DbSet<Blog> Blogs { get; set; }
+
+        [DbFunction("TableFunction")]
+        public IQueryable<TableFunction> TableFunction()
+            => FromExpression(() => TableFunction());
+
+        protected override void OnModelCreating(ModelBuilder modelBuilder)
+        {
+        }
+    }
+
+    private class Blog
+    {
+        public int Id { get; set; }
+    }
+
+    private class TableFunction
+    {
+        public int Id { get; set; }
+        public int BlogId { get; set; }
+        public Blog Blog { get; set; }
+    }
+}