types: fix unsigned decimal check and negative overflow bugs (pingcap…

…#6721)
doerjiayi · Jun 4, 2018 · 30f1601 · 30f1601
1 parent 64e3aca
commit 30f1601
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Showing 4 changed files with 61 additions and 0 deletions.
diff --git a/executor/executor_test.go b/executor/executor_test.go
@@ -2787,3 +2787,53 @@ func (s *testSuite) TestYearTypeDeleteIndex(c *C) {
 	tk.MustExec("delete from t;")
 	tk.MustExec("admin check table t")
 }
+
+func (s *testSuite) TestUnsignedDecimalOverflow(c *C) {
+	tests := []struct {
+		input  interface{}
+		hasErr bool
+		err    string
+	}{{
+		-1,
+		true,
+		"Out of range value for column",
+	}, {
+		"-1.1e-1",
+		true,
+		"Out of range value for column",
+	}, {
+		-1.1,
+		true,
+		"Out of range value for column",
+	}, {
+		-0,
+		false,
+		"",
+	},
+	}
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t")
+	tk.MustExec("create table t(a decimal(10,2) unsigned)")
+	for _, t := range tests {
+		res, err := tk.Exec("insert into t values (?)", t.input)
+		if res != nil {
+			defer res.Close()
+		}
+		if t.hasErr {
+			c.Assert(err, NotNil)
+			c.Assert(strings.Contains(err.Error(), t.err), IsTrue)
+		} else {
+			c.Assert(err, IsNil)
+		}
+		if res != nil {
+			res.Close()
+		}
+	}
+
+	tk.MustExec("set sql_mode=''")
+	tk.MustExec("delete from t")
+	tk.MustExec("insert into t values (?)", -1)
+	r := tk.MustQuery("select a from t limit 1")
+	r.Check(testkit.Rows("0.00"))
+}
diff --git a/types/datum.go b/types/datum.go
@@ -1077,6 +1077,12 @@ func (d *Datum) convertToMysqlDecimal(sc *stmtctx.StatementContext, target *Fiel
 	if err == nil && err1 != nil {
 		err = err1
 	}
+	if dec.negative && mysql.HasUnsignedFlag(target.Flag) {
+		*dec = zeroMyDecimal
+		if err == nil {
+			err = ErrOverflow.GenByArgs("DECIMAL", fmt.Sprintf("(%d, %d)", target.Flen, target.Decimal))
+		}
+	}
 	ret.SetValue(dec)
 	return ret, errors.Trace(err)
 }

diff --git a/types/mydecimal.go b/types/mydecimal.go
@@ -400,7 +400,9 @@ func (d *MyDecimal) FromString(str []byte) error {
 			}
 		}
 		if exponent > math.MaxInt32/2 {
+			negative := d.negative
 			maxDecimal(wordBufLen*digitsPerWord, 0, d)
+			d.negative = negative
 			err = ErrOverflow
 		}
 		if exponent < math.MinInt32/2 && err != ErrOverflow {
@@ -411,7 +413,9 @@ func (d *MyDecimal) FromString(str []byte) error {
 			shiftErr := d.Shift(int(exponent))
 			if shiftErr != nil {
 				if shiftErr == ErrOverflow {
+					negative := d.negative
 					maxDecimal(wordBufLen*digitsPerWord, 0, d)
+					d.negative = negative
 				}
 				err = shiftErr
 			}

diff --git a/types/mydecimal_test.go b/types/mydecimal_test.go
@@ -381,6 +381,7 @@ func (s *testMyDecimalSuite) TestFromString(c *C) {
 		{"123E5", "12300000", nil},
 		{"123E-2", "1.23", nil},
 		{"1e1073741823", "999999999999999999999999999999999999999999999999999999999999999999999999999999999", ErrOverflow},
+		{"-1e1073741823", "-999999999999999999999999999999999999999999999999999999999999999999999999999999999", ErrOverflow},
 		{"1e18446744073709551620", "0", ErrBadNumber},
 		{"1e", "1", ErrTruncated},
 		{"1e001", "10", nil},