codegen: test fixture factories now use randomness to generate unique column values

pkg/codegen/modelgenerate/generate_testfile.go

@@ -101,12 +101,55 @@ func GenerateModelTestAST(tbl pkgschema.Table, schema pkgschema.Schema, gomodNam
 
 	hasCreatedAt, hasUpdatedAt := tbl.HasAutoTimestamps()
 	updateTestFields := UpdateTestFields(tbl)
+	uniqueColumns := map[string]bool{}
+	for _, index := range schema.Indexes {
+		if index.TableName != tbl.TableName || !index.IsUnique {
+			continue
+		}
+		for _, columnName := range index.Columns {
+			uniqueColumns[columnName] = true
+		}
+	}
+	hasRandomUniqueField := false
+	for _, c := range updateTestFields {
+		if uniqueColumns[c.Name] {
+			hasRandomUniqueField = true
+			break
+		}
+	}
+	requiredForeignKeys := []pkgschema.Column{}
+	for _, c := range tbl.Columns {
+		// Only ordinary object foreign keys use a distinct TargetObjectID Go type;
+		// code-table foreign keys retain their underlying SQLite type in the generated model.
+		if c.IsNotNull && c.IsNonCodeTableForeignKey() {
+			requiredForeignKeys = append(requiredForeignKeys, c)
+		}
+	}
+	requiredForeignKeyParamNames := paramNamesFor(requiredForeignKeys)
+
+	// Calls made by this generated test do not create related objects themselves. Pass a
+	// zero ID so the generated test remains syntactically valid; callers of MakeXyz provide
+	// IDs of the related objects they create.
+	makeItemArgs := func() (ret []ast.Expr) {
+		for range requiredForeignKeys {
+			ret = append(ret, &ast.BasicLit{Kind: token.INT, Value: "0"})
+		}
+		return
+	}()
 
 	// func MakeItem() Item { return Item{} }
 	makeItemFunc := &ast.FuncDecl{
 		Name: makeHelperName,
 		Type: &ast.FuncType{
-			Params: &ast.FieldList{},
+			Params: &ast.FieldList{List: func() (ret []*ast.Field) {
+				for i, c := range requiredForeignKeys {
+					ret = append(ret, &ast.Field{
+						Names: []*ast.Ident{ast.NewIdent(requiredForeignKeyParamNames[i])},
+						Type:  GoTypeForColumn(c),
+					})
+				}
+				return
+			}()},
 			Results: &ast.FieldList{
 				List: []*ast.Field{
 					{Type: ast.NewIdent(tbl.GoTypeName)},
@@ -114,16 +157,62 @@ func GenerateModelTestAST(tbl pkgschema.Table, schema pkgschema.Schema, gomodNam
 			},
 		},
 		Body: &ast.BlockStmt{
-			List: []ast.Stmt{
+			List: append(
+				func() []ast.Stmt {
+					if !hasRandomUniqueField {
+						return nil
+					}
+					return []ast.Stmt{&ast.AssignStmt{
+						Lhs: []ast.Expr{ast.NewIdent("id")},
+						Tok: token.DEFINE,
+						Rhs: []ast.Expr{&ast.CallExpr{Fun: &ast.SelectorExpr{X: ast.NewIdent("rand"), Sel: ast.NewIdent("Int")}}},
+					}}
+				}(),
+				[]ast.Stmt{
 					&ast.ReturnStmt{
 						Results: []ast.Expr{
 							&ast.CompositeLit{
 								Type: ast.NewIdent(tbl.GoTypeName),
 								Elts: func() (ret []ast.Expr) {
-								for _, c := range updateTestFields {
+									// `UpdateTestFields()` skips foreign keys, so this will not cause duplicates
+									for i, c := range requiredForeignKeys {
 										ret = append(ret, &ast.KeyValueExpr{
 											Key:   ast.NewIdent(c.GoFieldName()),
-										Value: SampleValue(c, 0),
+											Value: ast.NewIdent(requiredForeignKeyParamNames[i]),
+										})
+									}
+									for _, c := range updateTestFields {
+										value := SampleValue(c, 0)
+										if uniqueColumns[c.Name] {
+											switch c.Type {
+											case "integer", "int":
+												value = ast.NewIdent("id")
+											case "text":
+												value = &ast.CallExpr{
+													Fun: &ast.SelectorExpr{X: ast.NewIdent("fmt"), Sel: ast.NewIdent("Sprintf")},
+													Args: []ast.Expr{
+														&ast.BasicLit{Kind: token.STRING, Value: `"%s-%d"`},
+														SampleValue(c, 0),
+														ast.NewIdent("id"),
+													},
+												}
+											case "blob":
+												value = &ast.CallExpr{
+													Fun: &ast.ArrayType{Elt: ast.NewIdent("byte")},
+													Args: []ast.Expr{&ast.CallExpr{
+														Fun: &ast.SelectorExpr{X: ast.NewIdent("fmt"), Sel: ast.NewIdent("Sprintf")},
+														Args: []ast.Expr{
+															&ast.BasicLit{Kind: token.STRING, Value: `"%s-%d"`},
+															&ast.CallExpr{Fun: ast.NewIdent("string"), Args: []ast.Expr{SampleValue(c, 0)}},
+															ast.NewIdent("id"),
+														},
+													}},
+												}
+											}
+										}
+										ret = append(ret, &ast.KeyValueExpr{
+											Key:   ast.NewIdent(c.GoFieldName()),
+											Value: value,
 										})
 									}
 									return
@@ -131,7 +220,8 @@ func GenerateModelTestAST(tbl pkgschema.Table, schema pkgschema.Schema, gomodNam
 							},
 						},
 					},
-			},
+				}...,
+			),
 		},
 	}
 
@@ -243,6 +333,7 @@ func GenerateModelTestAST(tbl pkgschema.Table, schema pkgschema.Schema, gomodNam
 							Rhs: []ast.Expr{
 								&ast.CallExpr{
 									Fun:  ast.NewIdent("Make" + tbl.GoTypeName),
+									Args: makeItemArgs,
 								},
 							},
 						},
@@ -329,7 +420,7 @@ func GenerateModelTestAST(tbl pkgschema.Table, schema pkgschema.Schema, gomodNam
 					&ast.AssignStmt{
 						Lhs: []ast.Expr{testObj},
 						Tok: token.DEFINE,
-						Rhs: []ast.Expr{&ast.CallExpr{Fun: makeHelperName, Args: nil}},
+						Rhs: []ast.Expr{&ast.CallExpr{Fun: makeHelperName, Args: makeItemArgs}},
 					},
 					// item.Description = <sample value, offset 1>
 					// ...one assignment per updatable field
@@ -560,7 +651,15 @@ func GenerateModelTestAST(tbl pkgschema.Table, schema pkgschema.Schema, gomodNam
 		Decls: append([]ast.Decl{
 			&ast.GenDecl{
 				Tok: token.IMPORT,
-				Specs: []ast.Spec{
+				Specs: func() []ast.Spec {
+					specs := []ast.Spec{}
+					if hasRandomUniqueField {
+						specs = append(specs,
+							&ast.ImportSpec{Path: &ast.BasicLit{Kind: token.STRING, Value: `"fmt"`}},
+							&ast.ImportSpec{Path: &ast.BasicLit{Kind: token.STRING, Value: `"math/rand"`}},
+						)
+					}
+					specs = append(specs, []ast.Spec{
 						&ast.ImportSpec{Path: &ast.BasicLit{Kind: token.STRING, Value: `"testing"`}},
 						&ast.ImportSpec{
 							Path: &ast.BasicLit{Kind: token.STRING, Value: `"git.offline-twitter.com/offline-labs/gas-stack/pkg/db"`},
@@ -576,7 +675,9 @@ func GenerateModelTestAST(tbl pkgschema.Table, schema pkgschema.Schema, gomodNam
 						&ast.ImportSpec{Path: &ast.BasicLit{Kind: token.STRING, Value: `"github.com/go-test/deep"`}},
 						&ast.ImportSpec{Path: &ast.BasicLit{Kind: token.STRING, Value: `"github.com/stretchr/testify/assert"`}},
 						&ast.ImportSpec{Path: &ast.BasicLit{Kind: token.STRING, Value: `"github.com/stretchr/testify/require"`}},
-				},
+					}...)
+					return specs
+				}(),
 			},
 		}, testList...),
 	}