Move string escaping methods from helpers to connection unit, replace code in TMySQLConnection.EscapeString(). So we don't use two different methods for the same task. Also, EscapeString() converted WideStrings into Strings using Utf8Encode, which was then displayed as broken text in SQL log.

source/helpers.pas

@@ -187,7 +187,7 @@ type
   function MakeInt( Str: String ) : Int64;
   function MakeFloat( Str: String ): Extended;
   function CleanupNumber(Str: String): String;
-  function esc(Text: WideString; ProcessJokerChars: Boolean = false; sql_version: integer = 50000): WideString;
+  function esc(Text: WideString; ProcessJokerChars: Boolean=false): WideString;
   function ScanNulChar(Text: WideString): Boolean;
   function ScanLineBreaks(Text: WideString): TLineBreaks;
   function RemoveNulChars(Text: WideString): WideString;
@@ -1563,109 +1563,12 @@ begin
 end;
 
 
-{***
- Attempt to do string replacement faster than StringReplace and WideStringReplace.
-}
-function escChars(const Text: WideString; EscChar, Char1, Char2, Char3, Char4: WideChar): WideString;
-const
-  // Attempt to match whatever the CPU cache will hold.
-  block: Cardinal = 65536;
-var
-  bstart, bend, matches, i: Cardinal;
-  // These could be bumped to uint64 if necessary.
-  len, respos: Cardinal;
-  next: WideChar;
+function esc(Text: WideString; ProcessJokerChars: Boolean=false): WideString;
 begin
-  len := Length(Text);
-  Result := '';
-  bend := 0;
-  respos := 0;
-  repeat
-    bstart := bend + 1;
-    bend := bstart + block - 1;
-    if bend > len then bend := len;
-    matches := 0;
-    for i := bstart to bend do if
-      (Text[i] = Char1) or
-      (Text[i] = Char2) or
-      (Text[i] = Char3) or
-      (Text[i] = Char4)
-    then Inc(matches);
-    SetLength(Result, bend + 1 - bstart + matches + respos);
-    for i := bstart to bend do begin
-      next := Text[i];
-      if
-        (next = Char1) or
-        (next = Char2) or
-        (next = Char3) or
-        (next = Char4)
-      then begin
-        Inc(respos);
-        Result[respos] := EscChar;
-        // Special values for MySQL escape.
-        if next = #13 then next := 'r';
-        if next = #10 then next := 'n';
-        if next = #0 then next := '0';
-      end;
-      Inc(respos);
-      Result[respos] := next;
-    end;
-  until bend = len;
+  Mainform.Connection.EscapeString(Text, ProcessJokerChars);
 end;
 
 
-{***
-  Escape all kinds of characters:
-  - single-backslashes which represent normal parts of the text and not escape-sequences
-  - characters which MySQL doesn't strictly care about, but which might confuse editors etc.
-  - single and double quotes in a text string
-  - joker-chars for LIKE-comparisons
-  Finally, surround the text by single quotes.
-
-  @param string Text to escape
-  @param boolean Escape text so it can be used in a LIKE-comparison
-  @return string
-}
-function esc(Text: WideString; ProcessJokerChars: Boolean = false; sql_version: integer = 50000): WideString;
-var
-  c1, c2, c3, c4, EscChar: WideChar;
-begin
-  c1 := '''';
-  c2 := '\';
-  c3 := '%';
-  c4 := '_';
-  EscChar := '\';
-  if (not ProcessJokerChars) or (sql_version = SQL_VERSION_ANSI) then begin
-    // Do not escape joker-chars which are used in a LIKE-clause
-    c4 := '''';
-    c3 := '''';
-  end;
-  if sql_version = SQL_VERSION_ANSI then begin
-    c2 := '''';
-    EscChar := '''';
-  end;
-  Result := escChars(Text, EscChar, c1, c2, c3, c4);
-  if sql_version <> SQL_VERSION_ANSI then begin
-    // Remove characters that SynEdit chokes on, so that
-    // the SQL file can be non-corruptedly loaded again.
-    c1 := #13;
-    c2 := #10;
-    c3 := #0;
-    c4 := #0;
-    // TODO: SynEdit also chokes on WideChar($2028) and possibly WideChar($2029).
-    Result := escChars(Result, EscChar, c1, c2, c3, c4);
-  end;
-  if not ProcessJokerChars then begin
-    // Add surrounding single quotes only for non-LIKE-values
-    // because in all cases we're using ProcessLIKEChars we
-    // need to add leading and/or trailing joker-chars by hand
-    // without being escaped
-    Result := WideChar(#39) + Result + WideChar(#39);
-  end;
-end;
-
-
-
 {***
   Detect NUL character in a text.
   Useful because fx SynEdit cuts of all text after it encounters a NUL.