Bug 239306 – Replace calls to substring(0, x) with the more concise left(x)

• Component: WebCore Misc.
• Status: RESOLVED FIXED

[Chris Dumez]

Replace calls to substring(0, x) with the more concise left(x).

[Chris Dumez]

Created attachment 457572 [details]
Patch

[Chris Dumez]

Created attachment 457578 [details]
Patch

[Darin Adler]

Comment on attachment 457578 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=457578&action=review

> Source/WebCore/platform/network/MIMEHeader.cpp:75
> +        key = StringView(line).left(semiColonIndex).convertToASCIILowercase().stripWhiteSpace();

Seems *so* unlikely this (and the code above) really wants stripWhiteSpace. Almost certainly wants to strip based on some other definitions of spaces rather than "all Unicode whitespace". Should be MIME whitespace definition, which is probably like the HTML or HTTP whitespace definition.

Almost every call to stripWhiteSpace is a mistake.

Also cute that this capitalizes semicolon as if it was two words, or hyphenated.

> Source/WebCore/svg/SVGURIReference.cpp:72
>      URL kurl(base, fragmentIdentifier);

Ah, yes, "kurl".

> Source/WebCore/workers/service/server/SWServer.cpp:1271
> +    if (!scheme.startsWithIgnoringASCIICase("http"))

Nice one. Could use the even-more-optimized startsWithLettersIgnoringASCIICase.

> Source/WebKit/UIProcess/API/glib/InputMethodFilter.cpp:243
> +    auto cursorPositionUTF8 = cursorPosition != text.length() ? StringView(text).left(cursorPosition).utf8().length() : textUTF8.length();

Not great to call utf8().length() instead of an algorithm that can compute a UTF-8 length, without also allocating memory and copying the characters. But doesn’t need to be fixed right now.

[Chris Dumez]

Created attachment 457586 [details]
Patch

[Chris Dumez]

Created attachment 457588 [details]
Patch

[EWS]

Committed r292857 (249628@main): <https://commits.webkit.org/249628@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 457588 [details].

[Radar WebKit Bug Importer]

<rdar://problem/91734789>