codegen (refactor): move foreign key failure check lambda function generator to a helper func

pkg/codegen/modelgenerate/generate_model.go

@@ -82,37 +82,11 @@ func GenerateModelAST(table schema.Table) *ast.GenDecl {
 	}
 }
 
-// GenerateSaveItemFunc produces an AST for the SaveXyz() function of the model.
-// E.g., a table with `table.TypeName = "foods"` will produce a "SaveFood()" function.
-func GenerateSaveItemFunc(tbl schema.Table) *ast.FuncDecl {
-	insertCols := make([]string, 0, len(tbl.Columns))
-	insertVals := make([]string, 0, len(tbl.Columns))
-	updatePairs := make([]string, 0, len(tbl.Columns))
-
-	hasCreatedAt, hasUpdatedAt := tbl.HasAutoTimestamps()
-
-	// Assemble data for building SQL "insert" and "update" strings
-	for _, col := range tbl.Columns {
-		if col.Name == "rowid" {
-			continue
-		}
-		insertCols = append(insertCols, col.Name)
-		val := ":" + col.Name
-		if col.IsNullableForeignKey() {
-			val = fmt.Sprintf("nullif(%s, 0)", val)
-		}
-		insertVals = append(insertVals, val)
-		// created_at should not be updated after creation
-		if col.Name == "created_at" && hasCreatedAt {
-			continue
-		}
-		updatePairs = append(updatePairs, col.Name+"="+val)
-	}
-	insertStmt := fmt.Sprintf("\n\t\t    insert into %s (%s)\n\t\t         values (%s)\n\t\t", tbl.TableName, strings.Join(insertCols, ", "), strings.Join(insertVals, ", "))
-	updateStmt := fmt.Sprintf("\n\t\t    update %s\n\t\t       set %s\n\t\t     where rowid = :rowid\n\t\t", tbl.TableName, strings.Join(updatePairs, ",\n\t\t           "))
-
+// buildFKCheckLambda builds the `checkForeignKeyFailures := func(err error) error { ... }` AST.
+// Returns the assignment statement and whether any FK columns were found.
+func buildFKCheckLambda(tbl schema.Table) (*ast.AssignStmt, bool) {
 	hasFks := false
-	checkForeignKeyFailuresAssignment := &ast.AssignStmt{
+	stmt := &ast.AssignStmt{
 		Lhs: []ast.Expr{ast.NewIdent("checkForeignKeyFailures")},
 		Tok: token.DEFINE,
 		Rhs: []ast.Expr{
@@ -228,6 +202,39 @@ func GenerateSaveItemFunc(tbl schema.Table) *ast.FuncDecl {
 			},
 		},
 	}
+	return stmt, hasFks
+}
+
+// GenerateSaveItemFunc produces an AST for the SaveXyz() function of the model.
+// E.g., a table with `table.TypeName = "foods"` will produce a "SaveFood()" function.
+func GenerateSaveItemFunc(tbl schema.Table) *ast.FuncDecl {
+	insertCols := make([]string, 0, len(tbl.Columns))
+	insertVals := make([]string, 0, len(tbl.Columns))
+	updatePairs := make([]string, 0, len(tbl.Columns))
+
+	hasCreatedAt, hasUpdatedAt := tbl.HasAutoTimestamps()
+
+	// Assemble data for building SQL "insert" and "update" strings
+	for _, col := range tbl.Columns {
+		if col.Name == "rowid" {
+			continue
+		}
+		insertCols = append(insertCols, col.Name)
+		val := ":" + col.Name
+		if col.IsNullableForeignKey() {
+			val = fmt.Sprintf("nullif(%s, 0)", val)
+		}
+		insertVals = append(insertVals, val)
+		// created_at should not be updated after creation
+		if col.Name == "created_at" && hasCreatedAt {
+			continue
+		}
+		updatePairs = append(updatePairs, col.Name+"="+val)
+	}
+	insertStmt := fmt.Sprintf("\n\t\t    insert into %s (%s)\n\t\t         values (%s)\n\t\t", tbl.TableName, strings.Join(insertCols, ", "), strings.Join(insertVals, ", "))
+	updateStmt := fmt.Sprintf("\n\t\t    update %s\n\t\t       set %s\n\t\t     where rowid = :rowid\n\t\t", tbl.TableName, strings.Join(updatePairs, ",\n\t\t           "))
+
+	checkForeignKeyFailuresAssignment, hasFks := buildFKCheckLambda(tbl)
 
 	funcBody := &ast.BlockStmt{
 		List: func() []ast.Stmt {