Add support for custom temp directory

[danielrbradley]

Make it easy to use a local temp directory for better debugging.

• Check python install process works for python (re: pulumitest: support Python venv #124)
• Use same 0755 permissions for all Mkdir calls.

Readme extract

By default, your program is copied to a temporary directory before running to avoid modifying your source files or cluttering your working directory with temporary files. This will use an OS-specific temporary location by default but can be set to a custom directory using the opttest.TempDir(dir) option. Using an ignored directory within your repository can be useful for being able to locate any left-over folders retained from failed tests:

test := NewPulumiTest(t, filepath.Join("path", "to", "program"), opttest.TempDir(".temp"))

[thomas11]

The use case isn't clear to me yet.

being able to locate any left-over folders retained from failed tests

Why can we not locate them in the temp dir? The dir is logged, no?

[danielrbradley]

The use case isn't clear to me yet.

being able to locate any left-over folders retained from failed tests

Why can we not locate them in the temp dir? The dir is logged, no?

You can identify them via the logs, but it's a little more handy if the directory shows up directly in your IDE file tree rather than having to open a new IDE from the command line having copied and pasted the path (after distinguishing the right one in the logs). With VSCode too it's a little annoying as you get a security prompt when opening any new directory now too.

[danielrbradley]

Oh, also, this could actually be very useful too when running in CI - to write to a predictable location that we can then grab as a workflow asset on failure so we can see the failed scenario (and perhaps manually clean up if required).

[pulumi-bot]

This PR has been shipped in release v0.1.6.