RFR: 7903132: Replace casts with type test pattern

[Ethan McCue]

On Fri, 25 Mar 2022 15:04:05 GMT, Jorn Vernee <jvernee at openjdk.org> wrote:

>> Replaces a handful of casts following type tests with the equivalent pattern syntax.
>> 
>> I cannot create a matching issue, as I do not have an account on the bug tracker.
>
> src/main/java/org/openjdk/jextract/clang/Cursor.java line 243:
> 
>> 241:             return false;
>> 242:         }
>> 243:         return (Index_h.clang_equalCursors(cursor, otherCursor.cursor) != 0);
> 
> I think in these cases we can do better by merging the `instanceof` check above this in the condition. i.e.
> Suggestion:
> 
>         return other instanceof Cursor otherCursor
>             && (Index_h.clang_equalCursors(cursor, otherCursor.cursor) != 0);
> 
> 
> And similar for other places that are computing a boolean value, such as all the equals methods.

Strictly speaking, the whole method body could be merged into one expression. Its the realm of infinite bikesheds though, and I did not / do not know if there is a set of implicit style choices there.

> src/main/java/org/openjdk/jextract/impl/ClassSourceBuilder.java line 59:
> 
>> 57:     ClassSourceBuilder(JavaSourceBuilder enclosing, Kind kind, String name) {
>> 58:         this.enclosing = enclosing;
>> 59:         this.align = (enclosing instanceof ClassSourceBuilder enclosing) ? enclosing.align : 0;
> 
> This is resulting in a compilation error:
> 
> jextract\src\main\java\org\openjdk\jextract\impl\ClassSourceBuilder.java:59: error: variable enclosing is already defined in constructor ClassSourceBuilder(JavaSourceBuilder,Kind,String)
>         this.align = (enclosing instanceof ClassSourceBuilder enclosing) ? enclosing.align : 0;
> 
> Please build and test the patch locally on your machine as well, if you haven't done so already. (This should be done before suggesting changes).

So yes, 100% on me. But in my defense I am getting a particularly obtuse error before compilation and there isn't exactly someone to ask without pretense.


$ /usr/bin/clang --version
Apple clang version 13.1.6 (clang-1316.0.21.2)
Target: arm64-apple-darwin21.3.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin

---------------------

$ sh ./gradlew -Pjdk18_home=/Users/emccue/Library/Java/JavaVirtualMachines/openjdk-18/Contents/Home  clean verify

FAILURE: Build failed with an exception.

* Where:
Build file '/Users/emccue/Development/jextract/build.gradle' line: 13

* What went wrong:
A problem occurred evaluating root project 'jextract'.
> Could not get unknown property 'libclang_home' for root project 'jextract' of type org.gradle.api.Project.

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 297ms

---------------------

$ sh ./gradlew -Pjdk18_home=/Users/emccue/Library/Java/JavaVirtualMachines/openjdk-18/Contents/Home -Plibclang_home=/usr/bin/clang clean verify

FAILURE: Build failed with an exception.

* Where:
Build file '/Users/emccue/Development/jextract/build.gradle' line: 14

* What went wrong:
A problem occurred evaluating root project 'jextract'.
> Cannot invoke method getAt() on null object

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 287ms

---------------------

$ sh ./gradlew -Pjdk18_home=/Users/emccue/Library/Java/JavaVirtualMachines/openjdk-18/Contents/Home -Plibclang_home=/usr/bin/ clean verify

FAILURE: Build failed with an exception.

* Where:
Build file '/Users/emccue/Development/jextract/build.gradle' line: 14

* What went wrong:
A problem occurred evaluating root project 'jextract'.
> Cannot invoke method getAt() on null object

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 290ms

-------------

PR: https://git.openjdk.java.net/jextract/pull/5