[tarantool-patches] Re: [PATCH v5 2/6] sql: fix "PRAGMA parser_trace" result

[Mergen Imeev <imeevma@tarantool.org>]

Hi! Thank you for review! My answers, diff and new patch
below.

On Mon, Feb 04, 2019 at 04:06:31PM +0300, Vladislav Shpilevoy wrote:
> Hi! Thanks for the fixes!
> 
> >diff --git a/src/box/sql/pragma.c b/src/box/sql/pragma.c
> >index 5729fe6..476771d 100644
> >--- a/src/box/sql/pragma.c
> >+++ b/src/box/sql/pragma.c
> >@@ -569,18 +566,6 @@ sqlite3Pragma(Parse * pParse, Token * pId, /* First part of [schema.]id field */
> >          }
> >          break;
> >      }
> >-#ifndef NDEBUG
> 
> 1. New question - why it was NDEBUG, but became SQLITE_DEBUG?
>
Before this change, definition of pragma parser_trace was under
the condition that SQLITE_DEBUG was defined, but body of the
pragma was described under the condition that NDEBUG was
undefined. I decided that it would be right to do the same
condition for both parts of the pragma. I chose SQLITE_DEBUG
because other similar pragmas use it.

> >-    case PragTyp_PARSER_TRACE:{
> >-            if (zRight) {
> >-                if (sqlite3GetBoolean(zRight, 0)) {
> >-                    sqlite3ParserTrace(stdout, "parser: ");
> >-                } else {
> >-                    sqlite3ParserTrace(0, 0);
> >-                }
> >-            }
> >-            break;
> >-        }
> >-#endif
> >
> >          /*
> >           * Reinstall the LIKE and functions. The variant
> >diff --git a/test/sql/sql-debug.test.lua b/test/sql/sql-debug.test.lua
> >new file mode 100644
> >index 0000000..721ef19
> >--- /dev/null
> >+++ b/test/sql/sql-debug.test.lua
> 
> 2. Now the test does not touch engine, but it is still run twice
> with two engines in test config.

Fixed.

diff --git a/test/sql/engine.cfg b/test/sql/engine.cfg
index 0007d8d..0fed962 100644
--- a/test/sql/engine.cfg
+++ b/test/sql/engine.cfg
@@ -1,4 +1,7 @@
 {
+    "sql-debug.test.lua": {
+        "memtx": {"engine": "memtx"}
+    },
     "*": {
         "memtx": {"engine": "memtx"},
         "vinyl": {"engine": "vinyl"}

New patch:

commit 6fe25516a13c5ae48c54ce48eb51d00a4a3dc2c6
Author: Mergen Imeev <imeevma@gmail.com>
Date:   Wed Dec 12 22:16:33 2018 +0300

    sql: fix "PRAGMA parser_trace" result
    
    Currently PRAGMA parser_trace returns an empty table. This seems
    wrong, since other similar pragmas return their status. Fixed in
    the current patch.

diff --git a/src/box/sql/pragma.c b/src/box/sql/pragma.c
index 5729fe6..476771d 100644
--- a/src/box/sql/pragma.c
+++ b/src/box/sql/pragma.c
@@ -466,33 +466,30 @@ sqlite3Pragma(Parse * pParse, Token * pId,	/* First part of [schema.]id field */
 	switch (pPragma->ePragTyp) {
 
 	case PragTyp_FLAG:{
-			if (zRight == 0) {
-				setPragmaResultColumnNames(v, pPragma);
-				returnSingleInt(v,
-						(user_session->
-						 sql_flags & pPragma->iArg) !=
-						0);
-			} else {
-				int mask = pPragma->iArg;	/* Mask of bits to set
-								 * or clear.
-								 */
-
-				if (sqlite3GetBoolean(zRight, 0)) {
-					user_session->sql_flags |= mask;
-				} else {
-					user_session->sql_flags &= ~mask;
-				}
-
-				/* Many of the flag-pragmas modify the code
-				 * generated by the SQL * compiler (eg.
-				 * count_changes). So add an opcode to expire
-				 * all * compiled SQL statements after
-				 * modifying a pragma value.
-				 */
-				sqlite3VdbeAddOp0(v, OP_Expire);
+		if (zRight == NULL) {
+			setPragmaResultColumnNames(v, pPragma);
+			returnSingleInt(v, (user_session->sql_flags &
+					    pPragma->iArg) != 0);
+		} else {
+			/* Mask of bits to set or clear. */
+			int mask = pPragma->iArg;
+			bool is_pragma_set = sqlite3GetBoolean(zRight, 0);
+
+			if (is_pragma_set)
+				user_session->sql_flags |= mask;
+			else
+				user_session->sql_flags &= ~mask;
+#if defined(SQLITE_DEBUG)
+			if (mask == PARSER_TRACE_FLAG) {
+				if (is_pragma_set)
+					sqlite3ParserTrace(stdout, "parser: ");
+				else
+					sqlite3ParserTrace(0, 0);
 			}
-			break;
+#endif
 		}
+		break;
+	}
 
 	case PragTyp_TABLE_INFO:
 		sql_pragma_table_info(pParse, zRight);
@@ -569,18 +566,6 @@ sqlite3Pragma(Parse * pParse, Token * pId,	/* First part of [schema.]id field */
 		}
 		break;
 	}
-#ifndef NDEBUG
-	case PragTyp_PARSER_TRACE:{
-			if (zRight) {
-				if (sqlite3GetBoolean(zRight, 0)) {
-					sqlite3ParserTrace(stdout, "parser: ");
-				} else {
-					sqlite3ParserTrace(0, 0);
-				}
-			}
-			break;
-		}
-#endif
 
 		/*
 		 * Reinstall the LIKE and functions. The variant
diff --git a/src/box/sql/pragma.h b/src/box/sql/pragma.h
index fd76b49..4837923 100644
--- a/src/box/sql/pragma.h
+++ b/src/box/sql/pragma.h
@@ -14,7 +14,6 @@
 #define PragTyp_INDEX_LIST                    11
 #define PragTyp_STATS                         15
 #define PragTyp_TABLE_INFO                    17
-#define PragTyp_PARSER_TRACE                  24
 #define PragTyp_DEFAULT_ENGINE                25
 #define PragTyp_COMPOUND_SELECT_LIMIT         26
 
@@ -137,10 +136,10 @@ static const PragmaName aPragmaName[] = {
 	 /* iArg:      */ 0},
 #if defined(SQLITE_DEBUG)
 	{ /* zName:     */ "parser_trace",
-	 /* ePragTyp:  */ PragTyp_PARSER_TRACE,
-	 /* ePragFlg:  */ 0,
+	 /* ePragTyp:  */ PragTyp_FLAG,
+	 /* ePragFlg:  */ PragFlg_Result0 | PragFlg_NoColumns1,
 	 /* ColNames:  */ 0, 0,
-	 /* iArg:      */ 0},
+	 /* iArg:      */ PARSER_TRACE_FLAG},
 #endif
 	{ /* zName:     */ "query_only",
 	 /* ePragTyp:  */ PragTyp_FLAG,
diff --git a/src/box/sql/sqliteInt.h b/src/box/sql/sqliteInt.h
index 7ee2627..25bd89f 100644
--- a/src/box/sql/sqliteInt.h
+++ b/src/box/sql/sqliteInt.h
@@ -1547,6 +1547,8 @@ struct sqlite3 {
  * Possible values for the sqlite3.flags.
  */
 #define SQLITE_VdbeTrace      0x00000001	/* True to trace VDBE execution */
+/* Debug print info about SQL query as it parsed */
+#define PARSER_TRACE_FLAG     0x00000002
 #define SQLITE_FullColNames   0x00000004	/* Show full column names on SELECT */
 #define SQLITE_ShortColNames  0x00000040	/* Show short columns names */
 #define SQLITE_CountRows      0x00000080	/* Count rows changed by INSERT, */
diff --git a/test/sql/engine.cfg b/test/sql/engine.cfg
index 0007d8d..0fed962 100644
--- a/test/sql/engine.cfg
+++ b/test/sql/engine.cfg
@@ -1,4 +1,7 @@
 {
+    "sql-debug.test.lua": {
+        "memtx": {"engine": "memtx"}
+    },
     "*": {
         "memtx": {"engine": "memtx"},
         "vinyl": {"engine": "vinyl"}
diff --git a/test/sql/sql-debug.result b/test/sql/sql-debug.result
new file mode 100644
index 0000000..9388578
--- /dev/null
+++ b/test/sql/sql-debug.result
@@ -0,0 +1,23 @@
+remote = require('net.box')
+---
+...
+test_run = require('test_run').new()
+---
+...
+--
+-- gh-3832: Some statements do not return column type
+-- Check that "PRAGMA parser_trace" returns 0 or 1 if called
+-- without parameter.
+result = box.sql.execute('PRAGMA parser_trace')
+---
+...
+box.sql.execute('PRAGMA parser_trace = 1')
+---
+...
+box.sql.execute('PRAGMA parser_trace')
+---
+- - [1]
+...
+box.sql.execute('PRAGMA parser_trace = '.. result[1][1])
+---
+...
diff --git a/test/sql/sql-debug.test.lua b/test/sql/sql-debug.test.lua
new file mode 100644
index 0000000..721ef19
--- /dev/null
+++ b/test/sql/sql-debug.test.lua
@@ -0,0 +1,12 @@
+remote = require('net.box')
+test_run = require('test_run').new()
+
+--
+-- gh-3832: Some statements do not return column type
+
+-- Check that "PRAGMA parser_trace" returns 0 or 1 if called
+-- without parameter.
+result = box.sql.execute('PRAGMA parser_trace')
+box.sql.execute('PRAGMA parser_trace = 1')
+box.sql.execute('PRAGMA parser_trace')
+box.sql.execute('PRAGMA parser_trace = '.. result[1][1])
diff --git a/test/sql/suite.ini b/test/sql/suite.ini
index 4504731..ce6ccb7 100644
--- a/test/sql/suite.ini
+++ b/test/sql/suite.ini
@@ -6,4 +6,4 @@ use_unix_sockets = True
 config = engine.cfg
 is_parallel = True
 lua_libs = lua/sql_tokenizer.lua
-release_disabled = errinj.test.lua view_delayed_wal.test.lua
+release_disabled = errinj.test.lua view_delayed_wal.test.lua sql-debug.test.lua