Improves error handling.

function.go

@@ -117,7 +117,7 @@ func (c *FunctionContext) Result(r interface{}) {
 	case Errno:
 		c.ResultErrorCode(r)
 	default:
-		panic(fmt.Sprintf("unsupported type in Result: %s", reflect.TypeOf(r)))
+		panic(fmt.Sprintf("unsupported type in Result: %q", reflect.TypeOf(r)))
 	}
 }
 

sqlite.go

@@ -30,9 +30,9 @@ import (
 
 type ConnError struct {
 	c       *Conn
-	code    Errno
-	msg     string
-	details string
+	code    Errno  // thread safe error code
+	msg     string // it might be the case that a second error occurs on a separate thread in between the time of the first error and the call to retrieve this message.
+	details string // contextual informations, thread safe
 }
 
 func (e *ConnError) Code() Errno {
@@ -51,9 +51,9 @@ func (e *ConnError) Filename() string {
 
 func (e *ConnError) Error() string { // FIXME code.Error() & e.msg are often redundant...
 	if len(e.details) > 0 {
-		return fmt.Sprintf("%s; %s (%s)", e.code.Error(), e.msg, e.details)
+		return fmt.Sprintf("%s (%s) (%s)", e.msg, e.details, e.code.Error())
 	} else if len(e.msg) > 0 {
-		return fmt.Sprintf("%s; %s", e.code.Error(), e.msg)
+		return fmt.Sprintf("%s (%s)", e.msg, e.code.Error())
 	}
 	return e.code.Error()
 }
@@ -66,7 +66,7 @@ func (e Errno) Error() string {
 	if e == ErrSpecific {
 		s = "Wrapper specific error"
 	} else {
-		s = C.GoString(C.sqlite3_errstr(C.int(e)))
+		s = C.GoString(C.sqlite3_errstr(C.int(e))) // thread safe
 	}
 	if s == "" {
 		return fmt.Sprintf("errno %d", int(e))
@@ -297,7 +297,7 @@ func (c *Conn) Readonly(dbName string) (bool, error) {
 	defer C.free(unsafe.Pointer(cname))
 	rv := C.sqlite3_db_readonly(c.db, cname)
 	if rv == -1 {
-		return false, c.error(C.SQLITE_ERROR, fmt.Sprintf("%q is not the name of a database", dbName))
+		return false, c.specificError("%q is not the name of a database", dbName)
 	}
 	return rv == 1, nil
 }

sqlite_test.go

@@ -196,7 +196,7 @@ func TestConnExecWithSelect(t *testing.T) {
 	err := db.Exec("SELECT 1")
 	assert.T(t, err != nil, "error expected")
 	if serr, ok := err.(*StmtError); ok {
-		assert.Equal(t, Row, serr.Code())
+		assert.Equal(t, ErrSpecific, serr.Code())
 	} else {
 		t.Errorf("Expected StmtError but got %s", reflect.TypeOf(err))
 	}
@@ -244,6 +244,7 @@ func TestExecMisuse(t *testing.T) {
 	createTable(db, t)
 	err := db.Exec("INSERT INTO test VALUES (?, ?, ?, ?); INSERT INTO test VALUES (?, ?, ?, ?)", 0, 273.1, 1, "test")
 	assert.T(t, err != nil, "exec misuse expected")
+	//println(err.Error())
 }
 
 func TestTransaction(t *testing.T) {

stmt.go

@@ -159,7 +159,7 @@ func (s *Stmt) exec() error {
 	err := Errno(rv)
 	if err != Done {
 		if err == Row {
-			return s.error(rv, "Don't use exec with anything that returns data such as SELECT")
+			return s.specificError("Don't use exec with anything that returns data such as SELECT")
 		}
 		return s.error(rv, "Stmt.exec")
 	}
@@ -603,7 +603,7 @@ func (s *Stmt) ColumnIndex(name string) (int, error) {
 	if ok {
 		return index, nil
 	}
-	return -1, s.specificError("invalid column name: %s", name)
+	return -1, s.specificError("invalid column name: %q", name)
 }
 
 // ScanByName scans result value from a query.
@@ -1059,14 +1059,14 @@ func (s *Stmt) checkTypeMismatch(source, target Type) error {
 		case Text:
 			fallthrough
 		case Blob:
-			return s.specificError("type mismatch, source %s vs target %s", source, target)
+			return s.specificError("type mismatch, source %q vs target %q", source, target)
 		}
 	case Float:
 		switch source {
 		case Text:
 			fallthrough
 		case Blob:
-			return s.specificError("type mismatch, source %s vs target %s", source, target)
+			return s.specificError("type mismatch, source %q vs target %q", source, target)
 		}
 	}
 	return nil

stmt_test.go

@@ -137,6 +137,7 @@ func TestNamedScanColumn(t *testing.T) {
 
 	_, err = s.ScanByName("invalid", &i1)
 	assert.T(t, err != nil, "expected invalid name")
+	//println(err.Error())
 }
 
 func TestScanCheck(t *testing.T) {
@@ -270,8 +271,9 @@ func TestStmtExecWithSelect(t *testing.T) {
 
 	err = s.Exec()
 	assert.T(t, err != nil, "error expected")
+	//println(err.Error())
 	if serr, ok := err.(*StmtError); ok {
-		assert.Equal(t, Row, serr.Code())
+		assert.Equal(t, ErrSpecific, serr.Code())
 	} else {
 		t.Errorf("Expected StmtError but got %s", reflect.TypeOf(err))
 	}