[perl #40729] [TODO] Tcl - implement 'ext' sub in runtime/builtin/file.pir

[Paul Cochrane]

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Implement the stub routine 'ext' in languages/tcl/runtime/builtin/file.pir

This ticket is in response to cage task #39704.

[Nuno Carvalho via RT]

Hi all,

This patch implements the first version of file ext for tcl. I am not
sure if it's supposed to be [file ext] or [file extension], i kept the
stub sub name 'ext' and so pushed 'ext' to the options
ResizablePMCArray. Feel free to change this.

It wasn't possible to test this using the test files, so i "hand made"
some tests using make tclsh:

% file ext
wrong # args: should be "file ext name"
% file ext abc.ddd
.ddd
% file ext foo
% file ext foo.bar
.bar
% file ext .bar
.bar
% file ext aaa.bbb.ccc.bar
.bar
% file ext .
.
% file ext aaa/bbb/ccc.foo
.foo
% file ext aaa\bbb\ccc.foo
.foo
% file ext aaa\aa.bb/ccc.dd
.dd
% file ext abc abc
wrong # args: should be "file ext name"
% file ext foo......bar
.bar

We can check for more stuff when we're able to use the test suit.

Files affected:
languages/tcl/runtime/builtin/file.pir

Best regards,
./smash