Add example for querying with function out parameters (#64)

The main trick is to SELECT FROM the function which converts the record
type into proper postgres columns.

Fixes #25.

example/acceptance_test.go

@@ -119,6 +119,14 @@ func TestExamples(t *testing.T) {
 				"--go-type", "tenant_id=int",
 			},
 		},
+		{
+			name: "example/function",
+			args: []string{
+				"--schema-glob", "example/function/schema.sql",
+				"--query-glob", "example/function/query.sql",
+				"--go-type", "hstore=map[string]string",
+			},
+		},
 		{
 			name: "example/go_pointer_types",
 			args: []string{

example/composite/query.sql_test.go

@@ -96,9 +96,9 @@ func TestNewQuerier_ArraysInput(t *testing.T) {
 	t.Run("ArraysInput", func(t *testing.T) {
 		want := Arrays{
 			Texts:  []string{"foo", "bar"},
-			Int8s:  []*int{ptrs.NewInt(1), ptrs.NewInt(2), ptrs.NewInt(3)},
+			Int8s:  []*int{ptrs.Int(1), ptrs.Int(2), ptrs.Int(3)},
 			Bools:  []bool{true, true, false},
-			Floats: []*float64{ptrs.NewFloat64(33.3), ptrs.NewFloat64(66.6)},
+			Floats: []*float64{ptrs.Float64(33.3), ptrs.Float64(66.6)},
 		}
 		got, err := q.ArraysInput(context.Background(), want)
 		require.NoError(t, err)

example/function/codegen_test.go

@@ -0,0 +1,44 @@
+package function
+
+import (
+	"github.com/jschaf/pggen"
+	"github.com/jschaf/pggen/internal/pgtest"
+	"github.com/stretchr/testify/assert"
+	"io/ioutil"
+	"path/filepath"
+	"testing"
+)
+
+func TestGenerate_Go_Example_Function(t *testing.T) {
+	conn, cleanupFunc := pgtest.NewPostgresSchema(t, []string{"schema.sql"})
+	defer cleanupFunc()
+
+	tmpDir := t.TempDir()
+	err := pggen.Generate(
+		pggen.GenerateOptions{
+			ConnString: conn.Config().ConnString(),
+			QueryFiles: []string{"query.sql"},
+			OutputDir:  tmpDir,
+			GoPackage:  "function",
+			Language:   pggen.LangGo,
+		})
+	if err != nil {
+		t.Fatalf("Generate() example/function: %s", err)
+	}
+
+	wantQueriesFile := "query.sql.go"
+	gotQueriesFile := filepath.Join(tmpDir, "query.sql.go")
+	assert.FileExists(t, gotQueriesFile,
+		"Generate() should emit query.sql.go")
+	wantQueries, err := ioutil.ReadFile(wantQueriesFile)
+	if err != nil {
+		t.Fatalf("read wanted query.go.sql: %s", err)
+	}
+	gotQueries, err := ioutil.ReadFile(gotQueriesFile)
+	if err != nil {
+		t.Fatalf("read generated query.go.sql: %s", err)
+	}
+	assert.Equalf(t, string(wantQueries), string(gotQueries),
+		"Got file %s; does not match contents of %s",
+		gotQueriesFile, wantQueriesFile)
+}

example/function/query.sql

@@ -0,0 +1,2 @@
+-- name: OutParams :many
+SELECT * FROM out_params();