Add Capacity/length methods for OsString.

[frewsxcv]

#29453

[rust-highfive]

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[nikomatsakis]

Looks pretty good to me, but it'd be good to add some tests I think (particular of clear, which has an obvious visible effect, but ideally you'd test the other methods too using unsafe code).

[alexcrichton]

Looks good to me as well! r=me with some tests like @nikomatsakis mentioned

[frewsxcv]

but ideally you'd test the other methods too using unsafe code

I know what unsafe means in the context of Rust, but I'm not sure why testing these methods would necessitate the usage of unsafe code? Do you have an example to get a better understanding of what you mean?

[alexcrichton]

I believe @nikomatsakis means testing the methods which themselves internally use unsafe (generally a good idea)

[frewsxcv]

Let me know how those tests look

[alexcrichton]

@bors: r+ 85aaa7b6df386d26509e6d4bebe9dd3246352510

Thanks!

[bors]

⌛ Testing commit 85aaa7b with merge 90c2f30...

[bors]

💔 Test failed - auto-win-msvc-32-opt

[frewsxcv]

Forgot to add a few intermediate methods (via Buf) for Windows. Just forced pushed the changes.

[alexcrichton]

@bors: r+ 8c3655b

[bors]

⌛ Testing commit 8c3655b with merge c2aa084...

[alexcrichton]

@bors: retry force

[bors]

⌛ Testing commit 8c3655b with merge 0cb2a7a...

[bors]

💔 Test failed - auto-linux-32-opt

[frewsxcv]

Test fail looks unrelated

[alexcrichton]

@bors: retry

On Fri, Feb 19, 2016 at 3:16 PM, Corey Farwell notifications@github.com
wrote:

Test fail looks unrelated

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Reply to this email directly or view it on GitHub
#31608 (comment).

[bors]

⌛ Testing commit 8c3655b with merge 4f3d588...

[bors]

💔 Test failed - auto-win-gnu-64-nopt-t

[frewsxcv]

Forgot to implement Buf::into_inner on the windows side. Latest force push fixes that.

[nikomatsakis]

@bors r+

[bors]

📌 Commit 29cac06 has been approved by nikomatsakis

[bors]

⌛ Testing commit 29cac06 with merge b00ad76...

[bors]

💔 Test failed - auto-win-msvc-32-opt

[frewsxcv]

Forgot the import. Added it in.

[alexcrichton]

@bors: r+ 2338d74

[bors]

⌛ Testing commit 2338d74 with merge 788a21e...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-debug-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-linux-cross-opt, auto-linux-musl-64-opt, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-mac-ios-opt, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-gnu-64-opt, auto-win-msvc-32-opt, auto-win-msvc-64-opt