Fixed bug#30059.

Server handles truncation for assignment of too-long values
into CHAR/VARCHAR/TEXT columns in a different ways when the
truncated characters are spaces:
1. CHAR(N) columns silently ignore end-space truncation;
2. TEXT columns post a truncation warning/error in the
   non-strict/strict mode.
3. VARCHAR columns always post a truncation note in
   any mode.

Space truncation processing has been synchronised over
CHAR/VARCHAR/TEXT columns: current behavior of VARCHAR
columns has been propagated as standard.

Binary-encoded string/BLOB columns are not affected.

mysql-test/r/heap.result

@@ -256,6 +256,7 @@ set @a=repeat(' ',20);
 insert into t1 values (concat('+',@a),concat('+',@a),concat('+',@a));
 Warnings:
 Note	1265	Data truncated for column 'v' at row 1
+Note	1265	Data truncated for column 'c' at row 1
 select concat('*',v,'*',c,'*',t,'*') from t1;
 concat('*',v,'*',c,'*',t,'*')
 *+ *+*+ *

mysql-test/r/innodb.result

@@ -1901,6 +1901,7 @@ set @a=repeat(' ',20);
 insert into t1 values (concat('+',@a),concat('+',@a),concat('+',@a));
 Warnings:
 Note	1265	Data truncated for column 'v' at row 1
+Note	1265	Data truncated for column 'c' at row 1
 select concat('*',v,'*',c,'*',t,'*') from t1;
 concat('*',v,'*',c,'*',t,'*')
 *+ *+*+ *

mysql-test/r/myisam.result

@@ -1104,6 +1104,7 @@ set @a=repeat(' ',20);
 insert into t1 values (concat('+',@a),concat('+',@a),concat('+',@a));
 Warnings:
 Note	1265	Data truncated for column 'v' at row 1
+Note	1265	Data truncated for column 'c' at row 1
 select concat('*',v,'*',c,'*',t,'*') from t1;
 concat('*',v,'*',c,'*',t,'*')
 *+ *+*+ *

mysql-test/r/strict.result

@@ -934,6 +934,8 @@ NULL	NULL
 DROP TABLE t1;
 CREATE TABLE t1 (col1 CHAR(5), col2 VARCHAR(6));
 INSERT INTO t1 VALUES ('hello', 'hello'),('he', 'he'),('hello   ', 'hello ');
+Warnings:
+Note	1265	Data truncated for column 'col1' at row 3
 INSERT INTO t1 (col1) VALUES ('hellobob');
 ERROR 22001: Data too long for column 'col1' at row 1
 INSERT INTO t1 (col2) VALUES ('hellobob');

mysql-test/r/type_binary.result

@@ -125,6 +125,7 @@ create table t1 (c char(2), vc varchar(2));
 insert into t1 values(0x4120, 0x4120);
 insert into t1 values(0x412020, 0x412020);
 Warnings:
+Note	1265	Data truncated for column 'c' at row 1
 Note	1265	Data truncated for column 'vc' at row 1
 drop table t1;
 set @old_sql_mode= @@sql_mode, sql_mode= 'traditional';

mysql-test/r/warnings.result

@@ -298,4 +298,42 @@ DROP TABLE t3;
 DROP PROCEDURE sp1;
 DROP PROCEDURE sp2;
 DROP PROCEDURE sp3;
+create table t1 (c_char char(255), c_varchar varchar(255), c_tinytext tinytext);
+create table t2 (c_tinyblob tinyblob);
+set @c = repeat(' ', 256);
+set @q = repeat('q', 256);
+set sql_mode = '';
+insert into t1 values(@c, @c, @c);
+Warnings:
+Note	1265	Data truncated for column 'c_char' at row 1
+Note	1265	Data truncated for column 'c_varchar' at row 1
+Note	1265	Data truncated for column 'c_tinytext' at row 1
+insert into t2 values(@c);
+Warnings:
+Warning	1265	Data truncated for column 'c_tinyblob' at row 1
+insert into t1 values(@q, @q, @q);
+Warnings:
+Warning	1265	Data truncated for column 'c_char' at row 1
+Warning	1265	Data truncated for column 'c_varchar' at row 1
+Warning	1265	Data truncated for column 'c_tinytext' at row 1
+insert into t2 values(@q);
+Warnings:
+Warning	1265	Data truncated for column 'c_tinyblob' at row 1
+set sql_mode = 'traditional';
+insert into t1 values(@c, @c, @c);
+Warnings:
+Note	1265	Data truncated for column 'c_char' at row 1
+Note	1265	Data truncated for column 'c_varchar' at row 1
+Note	1265	Data truncated for column 'c_tinytext' at row 1
+insert into t2 values(@c);
+ERROR 22001: Data too long for column 'c_tinyblob' at row 1
+insert into t1 values(@q, NULL, NULL);
+ERROR 22001: Data too long for column 'c_char' at row 1
+insert into t1 values(NULL, @q, NULL);
+ERROR 22001: Data too long for column 'c_varchar' at row 1
+insert into t1 values(NULL, NULL, @q);
+ERROR 22001: Data too long for column 'c_tinytext' at row 1
+insert into t2 values(@q);
+ERROR 22001: Data too long for column 'c_tinyblob' at row 1
+drop table t1, t2;
 End of 5.0 tests

mysql-test/t/warnings.test

@@ -212,4 +212,37 @@ DROP PROCEDURE sp1;
 DROP PROCEDURE sp2;
 DROP PROCEDURE sp3;
 
+
+#
+# Bug#30059: End-space truncation warnings are inconsistent or incorrect
+#
+
+create table t1 (c_char char(255), c_varchar varchar(255), c_tinytext tinytext);
+create table t2 (c_tinyblob tinyblob); # not affected by bug, for regression testing
+set @c = repeat(' ', 256);
+set @q = repeat('q', 256);
+
+set sql_mode = '';
+
+insert into t1 values(@c, @c, @c);
+insert into t2 values(@c);
+insert into t1 values(@q, @q, @q);
+insert into t2 values(@q);
+
+set sql_mode = 'traditional';
+
+insert into t1 values(@c, @c, @c);
+--error 1406
+insert into t2 values(@c);
+--error 1406
+insert into t1 values(@q, NULL, NULL);
+--error 1406
+insert into t1 values(NULL, @q, NULL);
+--error 1406
+insert into t1 values(NULL, NULL, @q);
+--error 1406
+insert into t2 values(@q);
+
+drop table t1, t2;
+
 --echo End of 5.0 tests

sql/field.cc

@@ -5861,26 +5861,41 @@ check_string_copy_error(Field_str *field,
 }
 
 
-
 /*
-  Send a truncation warning or a truncation error
-  after storing a too long character string info a field.
+  Check if we lost any important data and send a truncation error/warning
 
   SYNOPSIS
-    report_data_too_long()
-    field                    - Field
+    Field_longstr::report_if_important_data()
+    ptr                      - Truncated rest of string
+    end                      - End of truncated string
 
-  RETURN
-    N/A
+  RETURN VALUES
+    0   - None was truncated (or we don't count cut fields)
+    2   - Some bytes was truncated
+
+  NOTE
+    Check if we lost any important data (anything in a binary string,
+    or any non-space in others). If only trailing spaces was lost,
+    send a truncation note, otherwise send a truncation error.
 */
 
-inline void
-report_data_too_long(Field_str *field)
+int
+Field_longstr::report_if_important_data(const char *ptr, const char *end)
 {
-  if (field->table->in_use->abort_on_warning)
-    field->set_warning(MYSQL_ERROR::WARN_LEVEL_ERROR, ER_DATA_TOO_LONG, 1);
+  if ((ptr < end) && table->in_use->count_cuted_fields)
+  {
+    if (test_if_important_data(field_charset, ptr, end))
+    {
+      if (table->in_use->abort_on_warning)
+        set_warning(MYSQL_ERROR::WARN_LEVEL_ERROR, ER_DATA_TOO_LONG, 1);
       else
-    field->set_warning(MYSQL_ERROR::WARN_LEVEL_WARN, WARN_DATA_TRUNCATED, 1);
+        set_warning(MYSQL_ERROR::WARN_LEVEL_WARN, WARN_DATA_TRUNCATED, 1);
+    }
+    else /* If we lost only spaces then produce a NOTE, not a WARNING */
+      set_warning(MYSQL_ERROR::WARN_LEVEL_NOTE, WARN_DATA_TRUNCATED, 1);
+    return 2;
+  }
+  return 0;
 }
 
 
@@ -5914,19 +5929,7 @@ int Field_string::store(const char *from,uint length,CHARSET_INFO *cs)
                               cannot_convert_error_pos, from + length))
     return 2;
 
-  /*
-    Check if we lost any important data (anything in a binary string,
-    or any non-space in others).
-  */
-  if ((from_end_pos < from + length) && table->in_use->count_cuted_fields)
-  {
-    if (test_if_important_data(field_charset, from_end_pos, from + length))
-    {
-      report_data_too_long(this);
-      return 2;
-    }
-  }
-  return 0;
+  return report_if_important_data(from_end_pos, from + length);
 }
 
 
@@ -6385,16 +6388,7 @@ int Field_varstring::store(const char *from,uint length,CHARSET_INFO *cs)
                               cannot_convert_error_pos, from + length))
     return 2;
 
-  // Check if we lost something other than just trailing spaces
-  if ((from_end_pos < from + length) && table->in_use->count_cuted_fields)
-  {
-    if (test_if_important_data(field_charset, from_end_pos, from + length))
-      report_data_too_long(this);
-    else /* If we lost only spaces then produce a NOTE, not a WARNING */
-      set_warning(MYSQL_ERROR::WARN_LEVEL_NOTE, WARN_DATA_TRUNCATED, 1);
-    return 2;
-  }
-  return 0;
+  return report_if_important_data(from_end_pos, from + length);
 }
 
 
@@ -7030,13 +7024,7 @@ int Field_blob::store(const char *from,uint length,CHARSET_INFO *cs)
                               cannot_convert_error_pos, from + length))
     return 2;
 
-  if (from_end_pos < from + length)
-  {
-    report_data_too_long(this);
-    return 2;
-  }
-
-  return 0;
+  return report_if_important_data(from_end_pos, from + length);
 
 oom_error:
   /* Fatal OOM error */

sql/field.h

@@ -454,6 +454,8 @@ public:
 
 class Field_longstr :public Field_str
 {
+protected:
+  int report_if_important_data(const char *ptr, const char *end);
 public:
   Field_longstr(char *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
                 uchar null_bit_arg, utype unireg_check_arg,