[ac1982]

RunFile fails to open an existing absolute script path with the default compile options: resolveRunPath joins it to "." first, which removes the leading slash before the absolute-path check. With an empty sys.path, it never attempts the file at all.

Resolve absolute inputs independently of search directories by joining them only to an empty prefix. Relative-path search and existing error handling are unchanged. Add an execution regression using a real temporary script with both default options and an empty sys.path.

Fixes #259. This is independent of the nil-module-pointer fix in #260 and is based directly on main.

Validation on Linux/arm64:

• Both absolute-path cases fail with FileNotFoundError before the fix and pass afterward.
• Go 1.27.1 full project runner with -tags=ci -race -coverpkg=github.com/go-python/gpython/... passes.
• Go 1.18.10 targeted test and Staticcheck 2022.1.3 across all packages pass.
• goimports and git diff --check pass. Windows/macOS runtime behavior was not tested.

Author registration: go-python/license#24.

AI assistance: this fix and its regression tests were developed and verified with an AI coding agent.

[drew-512]

Tested against main (444ae5e): path.Join(".", "/tmp/script.py") cleans to tmp/script.py, so the absolute path gets retried under CurDir and the working directory and fails with FileNotFoundError, and with an empty sys.path nothing is tried at all. With this change, absolute paths resolve with CompileOpts{} and with UseSysPaths, a script run by absolute path can still import a module next to it, and relative paths with CurDir behave as before. The new test fails on main and passes here.

One coordination note: this PR and my #268 both added stdlib/stdlib_test.go, so whichever merged second would have conflicted. I've renamed the test in #268 to stdlib/moduleinit_test.go; the two now merge cleanly in either order.