Avoid fast-path in --sh-boot script when PEX_TOOLS=1 (#2726)

This patch stops the "execute venv entrypoint directly" fast-path from
happening when the user has set `PEX_TOOLS=1` with a `--sh-boot` PEX,
mimicking the similar check performed for Python bootstrapping:


https://github.com/pex-tool/pex/blob/17bd416647eaca978e538408f1ec21813ab26335/pex/pex_boot.py#L204-L205

This change ensures that `PEX_TOOLS=1 ./some.pex` always works, no
matter the state of the `PEX_ROOT` cache.

Fixes #2725

Author: huonw

CHANGES.md

@@ -1,5 +1,11 @@
 # Release Notes
 
+## 2.33.7
+
+This release fixes `PEX_TOOLS=1 ./path/to/pex` for PEXes using venv-execution and sh-bootstrapping (that is, built with `--sh-boot --venv=... --include-tools` ). Previously, the `PEX_TOOLS=1` was ignored if the venv already existed in the `PEX_ROOT` (for instance, if the PEX had already been run).
+
+* Avoid fast-path in `--sh-boot` script when `PEX_TOOLS=1`. (#2726)
+
 ## 2.33.6
 
 Fix PEP-723 script metadata parsing to skip metadata blocks found in multiline strings.

pex/sh_boot.py

@@ -199,10 +199,11 @@ def create_sh_boot_script(
         PEX_ROOT="${{PEX_ROOT:-${{DEFAULT_PEX_ROOT}}}}"
         INSTALLED_PEX="${{PEX_ROOT}}/{pex_installed_relpath}"
 
-        if [ -n "${{VENV}}" -a -x "${{INSTALLED_PEX}}" ]; then
+        if [ -n "${{VENV}}" -a -x "${{INSTALLED_PEX}}" -a -z "${{PEX_TOOLS:-}}" ]; then
             # We're a --venv execution mode PEX installed under the PEX_ROOT and the venv
             # interpreter to use is embedded in the shebang of our venv pex script; so just
-            # execute that script directly.
+            # execute that script directly... except if we're needing to execute PEX code, in
+            # the form of the tools.
             export PEX="{pex}"
             exec "${{INSTALLED_PEX}}/bin/python" ${{VENV_PYTHON_ARGS}} "${{INSTALLED_PEX}}" \\
                 "$@"

pex/version.py

@@ -1,4 +1,4 @@
 # Copyright 2015 Pex project contributors.
 # Licensed under the Apache License, Version 2.0 (see LICENSE).
 
-__version__ = "2.33.6"
+__version__ = "2.33.7"

tests/integration/test_sh_boot.py

@@ -310,3 +310,38 @@ def main():
         "pickling and other use cases as outlined in https://github.com/pex-tool/pex/issues/1018."
     )
     assert {} == data
+
+
+@execution_mode
+def test_issue_2726_pex_tools(
+    tmpdir,  # type: Any
+    execution_mode_args,  # type: List[str]
+):
+    # type: (...) -> None
+
+    pex = os.path.realpath(os.path.join(str(tmpdir), "pex.sh"))
+
+    run_pex_command(args=["-o", pex, "--include-tools"] + execution_mode_args).assert_success()
+
+    pex_root = os.path.join(str(tmpdir), "pex_root")
+
+    def _check_pex_tools():
+        output = subprocess.check_output(
+            args=[pex, "info"],
+            env=make_env(PEX_TOOLS=1, PEX_ROOT=pex_root),
+            stderr=subprocess.STDOUT,
+        )
+        # Check for output that implies we got sensible `PEX_TOOLS=1 ./some.pex info` output (a JSON
+        # object with specific keys):
+        info = json.loads(output)
+        assert "bootstrap_hash" in info
+        assert "pex_hash" in info
+
+    # run the tools with an empty/unseeded PEX_ROOT
+    _check_pex_tools()
+
+    # ensure the PEX_ROOT is fully seeded e.g. with a venv for venv execution mode
+    subprocess.check_output(args=[pex, "-c", ""], env=make_env(PEX_ROOT=pex_root))
+
+    # run the tools with seeded PEX_ROOT
+    _check_pex_tools()