pyoxidizer: ensure output directory exists before writing executable

Reported in #447. I can't believe this bug existed!

Author: indygreg

pyoxidizer/docs/pyoxidizer_history.rst

@@ -51,6 +51,9 @@ Bug Fixes
   the symbol. (#463)
 * Python ``.whl`` resources parsing now ignores directories. Previously,
   directories may have been emitted as 0-sized resources.
+* In some ``pyoxidizer.bzl`` configurations, an error would occur due to attempting
+  to write a built executable to a directory that doesn't exist. This should no
+  longer occur. (#447)
 
 Backwards Compatibility Notes
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

pyoxidizer/src/starlark/python_executable.rs

@@ -97,6 +97,9 @@ pub fn build_internal(
     let output_path = context
         .get_output_path(type_values, target)
         .map_err(|_| anyhow!("unable to resolve output path"))?;
+    std::fs::create_dir_all(&output_path)
+        .with_context(|| format!("creating output directory {}", output_path.display()))?;
+
     let dest_path = output_path.join(build.exe_name);
     warn!(
         context.logger(),