Write adhoc_tool(stdout/stderr="...") relative to workdir, support ab…

…solute paths (Cherry-pick of #18814) (#18839)

This fixes #18810 by ensuring `adhoc_tool(stdout="...", stderr="...")`
are written relative to the working directory, and before the
`root_output_directory` filtering happens.

This also fixes a second bug I noticed while working on this: if the
path is absolute, e.g. `stdout="/out.txt"`, pants crashes: ```panic at
'called `Result::unwrap()` on an `Err` value: "Absolute paths are not
allowed: \"/out.txt\""', src/intrinsics.rs:420```. After this PR, they
are supported, and taken to start at the build root.

src/python/pants/backend/adhoc/adhoc_tool.py

@@ -35,7 +35,7 @@
 from pants.core.util_rules.environments import EnvironmentNameRequest
 from pants.engine.addresses import Addresses
 from pants.engine.environment import EnvironmentName
-from pants.engine.fs import CreateDigest, Digest, FileContent, MergeDigests, Snapshot
+from pants.engine.fs import Digest, MergeDigests, Snapshot
 from pants.engine.internals.native_engine import EMPTY_DIGEST
 from pants.engine.rules import Get, collect_rules, rule
 from pants.engine.target import (
@@ -167,6 +167,8 @@ async def run_in_sandbox_request(
         supplied_env_var_values=FrozenDict(extra_env),
         log_on_process_errors=None,
         log_output=target[AdhocToolLogOutputField].value,
+        capture_stderr_file=target[AdhocToolStderrFilenameField].value,
+        capture_stdout_file=target[AdhocToolStdoutFilenameField].value,
     )
 
     adhoc_result = await Get(
@@ -177,23 +179,7 @@ async def run_in_sandbox_request(
         },
     )
 
-    result = adhoc_result.process_result
-    adjusted = adhoc_result.adjusted_digest
-
-    extras = (
-        (target[AdhocToolStdoutFilenameField].value, result.stdout),
-        (target[AdhocToolStderrFilenameField].value, result.stderr),
-    )
-    extra_contents = {i: j for i, j in extras if i}
-
-    if extra_contents:
-        extra_digest = await Get(
-            Digest,
-            CreateDigest(FileContent(name, content) for name, content in extra_contents.items()),
-        )
-        adjusted = await Get(Digest, MergeDigests((adjusted, extra_digest)))
-
-    output = await Get(Snapshot, Digest, adjusted)
+    output = await Get(Snapshot, Digest, adhoc_result.adjusted_digest)
     return GeneratedSources(output)
 
 

src/python/pants/backend/adhoc/adhoc_tool_test.py

@@ -141,29 +141,42 @@ def test_adhoc_tool_with_workdir(rule_runner: RuleRunner) -> None:
     )
 
 
-def test_adhoc_tool_capture_stdout_err(rule_runner: RuleRunner) -> None:
+@pytest.mark.parametrize(
+    ("write_dir", "workdir", "root_output_directory", "expected_dir"),
+    [
+        # various relative paths:
+        ("", None, None, "src/"),
+        ("dir/", None, None, "src/dir/"),
+        ("../", None, None, ""),
+        # absolute path
+        ("/", None, None, ""),
+        # interaction with workdir and root_output_directory:
+        ("", "/", None, ""),
+        ("dir/", None, ".", "dir/"),
+        ("3/", "1/2", "1", "2/3/"),
+    ],
+)
+def test_adhoc_tool_capture_stdout_err(
+    rule_runner: RuleRunner,
+    write_dir: str,
+    workdir: None | str,
+    root_output_directory: None | str,
+    expected_dir: str,
+) -> None:
     rule_runner.write_files(
         {
-            "src/fruitcake.py": dedent(
-                """\
-                import sys
-                print("fruitcake")
-                print("inconceivable", file=sys.stderr)
-                """
-            ),
             "src/BUILD": dedent(
-                """\
-                python_source(
-                    source="fruitcake.py",
-                    name="fruitcake",
-                )
+                f"""\
+                system_binary(name="bash", binary_name="bash")
 
                 adhoc_tool(
                   name="run_fruitcake",
-                  runnable=":fruitcake",
-                  stdout="stdout",
-                  stderr="stderr",
-                  root_output_directory=".",
+                  runnable=":bash",
+                  args=["-c", "echo fruitcake; echo inconceivable >&2"],
+                  stdout="{write_dir}stdout",
+                  stderr="{write_dir}stderr",
+                  workdir={workdir!r},
+                  root_output_directory={root_output_directory!r},
                 )
                 """
             ),
@@ -174,8 +187,8 @@ def test_adhoc_tool_capture_stdout_err(rule_runner: RuleRunner) -> None:
         rule_runner,
         Address("src", target_name="run_fruitcake"),
         expected_contents={
-            "stderr": "inconceivable\n",
-            "stdout": "fruitcake\n",
+            f"{expected_dir}stderr": "inconceivable\n",
+            f"{expected_dir}stdout": "fruitcake\n",
         },
     )
 

src/python/pants/backend/adhoc/target_types.py

@@ -154,8 +154,9 @@ class AdhocToolStdoutFilenameField(StringField):
     default = None
     help = help_text(
         lambda: f"""
-        A filename to capture the contents of `stdout` to, relative to the value of
-        `{AdhocToolWorkdirField.alias}`.
+        A filename to capture the contents of `stdout` to. Relative paths are
+        relative to the value of `{AdhocToolWorkdirField.alias}`, absolute paths
+        start at the build root.
         """
     )
 
@@ -165,8 +166,9 @@ class AdhocToolStderrFilenameField(StringField):
     default = None
     help = help_text(
         lambda: f"""
-        A filename to capture the contents of `stderr` to, relative to the value of
-        `{AdhocToolWorkdirField.alias}`
+        A filename to capture the contents of `stderr` to. Relative paths are
+        relative to the value of `{AdhocToolWorkdirField.alias}`, absolute paths
+        start at the build root.
         """
     )
 

src/python/pants/backend/shell/util_rules/shell_command.py

@@ -157,6 +157,8 @@ async def _prepare_process_request_from_target(
         immutable_input_digests=FrozenDict.frozen(merged_extras.immutable_input_digests),
         log_on_process_errors=_LOG_ON_PROCESS_ERRORS,
         log_output=shell_command[ShellCommandLogOutputField].value,
+        capture_stdout_file=None,
+        capture_stderr_file=None,
     )
 
 

src/python/pants/core/util_rules/adhoc_process_support.py

@@ -61,6 +61,8 @@ class AdhocProcessRequest:
     supplied_env_var_values: FrozenDict[str, str] | None
     log_on_process_errors: FrozenDict[int, str] | None
     log_output: bool
+    capture_stdout_file: str | None
+    capture_stderr_file: str | None
 
 
 @dataclass(frozen=True)
@@ -410,7 +412,25 @@ async def run_adhoc_process(
         request.root_output_directory, working_directory
     )
 
-    adjusted = await Get(Digest, RemovePrefix(result.output_digest, root_output_directory))
+    extras = (
+        (request.capture_stdout_file, result.stdout),
+        (request.capture_stderr_file, result.stderr),
+    )
+    extra_contents = {i: j for i, j in extras if i}
+
+    output_digest = result.output_digest
+
+    if extra_contents:
+        extra_digest = await Get(
+            Digest,
+            CreateDigest(
+                FileContent(_parse_relative_file(name, working_directory), content)
+                for name, content in extra_contents.items()
+            ),
+        )
+        output_digest = await Get(Digest, MergeDigests((output_digest, extra_digest)))
+
+    adjusted = await Get(Digest, RemovePrefix(output_digest, root_output_directory))
 
     return AdhocProcessResult(result, adjusted)
 
@@ -508,5 +528,15 @@ def _parse_relative_directory(workdir_in: str, relative_to: Union[Address, str])
         return workdir_in
 
 
+def _parse_relative_file(file_in: str, relative_to: str) -> str:
+    """Convert the `capture_std..._file` fields into something that can be understood by
+    `Process`."""
+
+    if file_in.startswith("/"):
+        return file_in[1:]
+
+    return os.path.join(relative_to, file_in)
+
+
 def rules():
     return collect_rules()