LazUtils: Resolve '/somedir/..' correctly in ResolveDots. Add tests. Issue #40678.

(cherry picked from commit 148b2d23f4)

components/lazutils/lazfileutils.inc

@@ -21,14 +21,13 @@ function ResolveDots(const AFilename: string): string;
     Result:=false;
   end;
 
-var SrcPos, DestPos, Len, DirStart: integer;
+var
+  SrcPos, DestPos, Len, DirStart: integer;
   c: char;
   MacroPos: LongInt;
-  ResultMustEndWithPathDelim: Boolean;
 begin
   Len:=length(AFilename);
   if Len=0 then exit('');
-
   Result:=AFilename;
 
   {$ifdef windows}
@@ -38,13 +37,6 @@ begin
     exit;
   {$endif}
 
-  //To add some consistency to the outcomes
-  //Depending on the path the algorithm takes it may remove the trailing PathDelim, so we restore it later if needed
-  //Issue #37188
-  //It's a workaround, fee free to implement a better fix
-  ResultMustEndWithPathDelim := ((Len>2) and (AFilename[Len]='.') and (AFilename[Len-1]='.') and (AFilename[Len-2] in AllowDirectorySeparators)) or
-                                ((Len>1) and (AFilename[Len]='.') and (AFilename[Len-1] in AllowDirectorySeparators));
-
   SrcPos:=1;
   DestPos:=1;
 
@@ -76,8 +68,7 @@ begin
       if (SrcPos<Len) then begin
         if (AFilename[SrcPos+1] in AllowDirectorySeparators)
         and IsPathDelim(Result,DestPos-1) then begin
-          // special dir ./ or */./
+          // special dir ./ or */./   -> skip
-          // -> skip
           inc(SrcPos,2);
           while (SrcPos<=Len) and (AFilename[SrcPos] in AllowDirectorySeparators) do
             inc(SrcPos);
@@ -145,12 +136,8 @@ begin
                 //writeln('ResolveDots ',DestPos,' SrcPos=',SrcPos,' File="',AFilename,'" Result="',copy(Result,1,DestPos-1),'"');
                 if SrcPos>Len then begin
                   // '..' at end of filename
-                  if (DestPos>1) and (Result[DestPos-1]=PathDelim) then begin
+                  if (DestPos=1) then begin
-                    // foo/dir/.. -> foo
+                    Result[1]:='.';  // foo/.. -> .
-                    dec(DestPos);
-                  end else if (DestPos=1) then begin
-                    // foo/.. -> .
-                    Result[1]:='.';
                     DestPos:=2;
                   end;
                 end else if DestPos=1 then begin
@@ -165,20 +152,8 @@ begin
         end;
       end else begin
         // special dir . at end of filename
-        if DestPos=1 then begin
+        if DestPos=1 then
-          Result:='.';
+          exit('.');
-          exit;
-        end;
-        if (DestPos>2) and (Result[DestPos-1]=PathDelim)
-        {$ifdef windows}
-        and not IsDriveDelim(Result,DestPos-2)
-        {$endif}
-        then begin
-          // foo/. -> foo
-          // C:foo\. -> C:foo
-          // C:\. -> C:\
-          {dec(DestPos); } //Part of issue #37188
-        end;
         break;
       end;
     end;
@@ -198,12 +173,10 @@ begin
   end;
   // trim result
   if DestPos<=length(AFilename) then
-    if (DestPos=1) then
+    if DestPos=1 then
       Result:='.'
     else
       SetLength(Result,DestPos-1);
-  if ResultMustEndWithPathDelim and (Result<>'.') and (Result[Length(Result)]<>PathDelim) then
-    Result := Result + PathDelim;
 end;
 
 function FilenameIsWinAbsolute(const TheFilename: string): boolean;

test/lazutils/testlazfileutils.pas

@@ -63,7 +63,7 @@ begin
   t('..','..');
   t('bla/..','.');
   t('bla//..','.');
-  t('foo/bla//..','foo');
+  t('foo/bla//..','foo/');
   t('bla/../','.');
   t('bla//..//','.');
   t('foo/../bar','bar');
@@ -82,6 +82,8 @@ begin
   t('.//.//.','.');
   t('foo/bar/./../too','foo/too');
   t('foo//bar//.//..//too','foo/too');
+  t('/bla/..','/');
+  t('/..','/');
   {$IFDEF Unix}
   t('/.','/');
   t('//.','/');
@@ -142,10 +144,12 @@ begin
   DoTest('a/../b','b');
   DoTest('a/b/../c','a/c');
   DoTest('a/b/../../c','c');
+  DoTest('a/b/c/../..','a/');
   DoTest('a/./b','a/b');
   DoTest('a/.//b','a/b');
   DoTest('a//b','a/b');
   DoTest('a//./b','a/b');
+  DoTest('/a/b/../..','/');
 end;
 
 procedure TTestLazFileUtils.TestCreateRelativePath;

test/runtests.lpi

@@ -178,6 +178,11 @@
         <StackChecks Value="True"/>
       </Checks>
     </CodeGeneration>
+    <Linking>
+      <Debugging>
+        <DebugInfoType Value="dsDwarf3"/>
+      </Debugging>
+    </Linking>
     <Other>
       <CustomOptions Value="-dNoSemiAutomatedTests"/>
     </Other>