Repair non-unix builds

There were a couple of unix-specifc API usages wrapped by `if cfg!(unix)`.
The problem with this approach is that although `if cfg!(unix)` will
prevent that branch from being taken on non-unix platforms at runtime, it
*does not* eliminate that branch at compile time. Thus any use of
unix-specific APIs within those blocks will cause compilation failure on
non-unix platforms.

The repair is to create unix and non-unix functions that are resolved at
compile time.

Author: jpgrayson

src/hook.rs

@@ -44,12 +44,9 @@ pub(crate) fn run_pre_commit_hook(repo: &git2::Repository, use_editor: bool) ->
         return Ok(());
     }
 
-    if cfg!(unix) {
-        use std::os::unix::fs::MetadataExt;
-        // Ignore non-executable hooks
-        if hook_meta.mode() & 0o111 == 0 {
-            return Ok(());
-        }
+    // Ignore non-executable hooks
+    if !is_executable(&hook_meta) {
+        return Ok(());
     }
 
     let mut hook_command = std::process::Command::new(hook_path);
@@ -105,12 +102,9 @@ pub(crate) fn run_commit_msg_hook<'repo>(
         return Ok(message);
     }
 
-    if cfg!(unix) {
-        use std::os::unix::fs::MetadataExt;
-        // Ignore non-executable hooks
-        if hook_meta.mode() & 0o111 == 0 {
-            return Ok(message);
-        }
+    // Ignore non-executable hooks
+    if !is_executable(&hook_meta) {
+        return Ok(message);
     }
 
     let mut msg_file = tempfile::NamedTempFile::new()?;
@@ -151,3 +145,14 @@ pub(crate) fn run_commit_msg_hook<'repo>(
         ))
     }
 }
+
+#[cfg(unix)]
+fn is_executable(meta: &std::fs::Metadata) -> bool {
+    use std::os::unix::fs::MetadataExt;
+    meta.mode() & 0o111 != 0
+}
+
+#[cfg(not(unix))]
+fn is_executable(_meta: &std::fs::Metadata) -> bool {
+    true
+}

src/stupid.rs

@@ -20,7 +20,7 @@ use std::{
     ffi::{OsStr, OsString},
     io::Write,
     path::Path,
-    process::{Child, Command, Output, Stdio},
+    process::{Child, Command, Output, ExitStatus, Stdio},
 };
 
 use anyhow::{anyhow, Context, Result};
@@ -638,14 +638,11 @@ impl<'repo, 'index> StupidContext<'repo, 'index> {
             command.args(pathspecs);
         }
         let output = command.stdout(Stdio::inherit()).output_git()?;
-        if cfg!(unix) {
-            use std::os::unix::process::ExitStatusExt;
-            if output.status.signal() == Some(13) {
-                // `git log` process was killed by SIGPIPE, probably due to pager exiting before
-                // all log output could be written. This is normal, but `git log` does not print an
-                // error message to stderr, so we inject our own error string.
-                return Err(git_command_error("log", b"broken pipe"));
-            }
+        if is_status_signal(&output.status, 13) {
+            // `git log` process was killed by SIGPIPE, probably due to pager exiting before
+            // all log output could be written. This is normal, but `git log` does not print an
+            // error message to stderr, so we inject our own error string.
+            return Err(git_command_error("log", b"broken pipe"));
         }
         output.require_success("log")?;
         Ok(())
@@ -1172,3 +1169,14 @@ fn parse_oid(output: &[u8]) -> Result<git2::Oid> {
 fn map_color_opt(opt: Option<&str>) -> Option<&str> {
     opt.map(|o| if o == "ansi" { "always" } else { o })
 }
+
+#[cfg(unix)]
+fn is_status_signal(status: &ExitStatus, signum: i32) -> bool {
+    use std::os::unix::process::ExitStatusExt;
+    status.signal() == Some(signum)
+}
+
+#[cfg(not(unix))]
+fn is_status_signal(_status: &ExitStatus, _signum: i32) -> bool {
+    false
+}