test(windows): run the Windows code under Wine; theme preview parity

Windows was previously only compile-checked. With Wine 11 (staging)
and mingw available, scripts/windows-wine-test.sh (`just
test-windows-wine`) builds expat/FreeType/fontconfig for mingw under
target/wine-deps and runs the test suites of ghostty-vt, unicode,
datastruct, input, os, config, terminal, crash, termio and cli under
Wine (~2,700 tests). New termio/tests/exec_windows.rs drives real
cmd.exe children over ConPTY through Termio (output, exit codes,
typing, 120 KiB writes, stop, start failure). Fixes found: Windows
paths from fs::canonicalize leaked the \\?\ prefix (new
ghostty_os::path::realpath strips it like Zig); ghostty-font compiles
hb-ft for bundled HarfBuzz on Windows; ~25 tests had Unix assumptions.
Wine limitations are ignored with reasons (ResizePseudoConsole stub,
no POSIX rename over existing files) - docs/rewrite/notes/windows-wine.md.

+list-themes preview parity (former KNOWN_DIFFERENCES rows 5-9): the
search box ports vaxis TextInput (word navigation and editing bindings,
grapheme-wise editing), ASCII-only case folding, light initial colors
until terminal reports arrive (no COLORFGBG), and load errors end the
preview with exit 1; PTY tests compare with /usr/bin/ghostty.

Test Plan:
- just test-windows-wine
- cargo test -p ghostty-cli --test list_themes_pty
- cargo test --workspace --no-fail-fast (3601 passed)

crates/ghostty-config/src/config.rs

@@ -4216,7 +4216,7 @@ impl Config {
 
         // Any paths referenced from the CLI are relative to the current working
         // directory.
-        let cwd = std::fs::canonicalize(".")?;
+        let cwd = crate::path::realpath(".")?;
         self.expand_paths(&EncodedOs::from_path(&cwd))?;
         Ok(())
     }
@@ -5115,12 +5115,22 @@ mod tests {
     fn write_theme(td: &TempDir, name: &str, data: &str) -> String {
         let p = td.path().join(name);
         std::fs::write(&p, data).unwrap();
-        std::fs::canonicalize(&p)
+        crate::path::realpath(&p)
             .unwrap()
             .to_string_lossy()
             .into_owned()
     }
 
+    /// A path as a `light:`/`dark:` pair value. Backslashes are escapes in
+    /// the pair syntax (as in Zig), so Windows paths must be quoted.
+    fn pair_value(path: &str) -> String {
+        if cfg!(windows) {
+            format!("\"{}\"", path.replace('\\', "\\\\"))
+        } else {
+            path.to_owned()
+        }
+    }
+
     #[test]
     fn handle_bom_in_config_files() {
         {
@@ -5223,7 +5233,11 @@ mod tests {
         let dark = write_theme(&td, "theme_dark", include_str!("testdata/theme_dark"));
 
         let mut cfg_light = Config::default();
-        let mut i = it(&[&format!("--theme=light:{light},dark:{dark}")]);
+        let mut i = it(&[&format!(
+            "--theme=light:{},dark:{}",
+            pair_value(&light),
+            pair_value(&dark)
+        )]);
         cfg_light.load_iter(&mut i).unwrap();
         cfg_light.finalize().unwrap();
 
@@ -5407,7 +5421,11 @@ mod tests {
         let td = TempDir::init().unwrap();
         let light = write_theme(&td, "theme_light", include_str!("testdata/theme_light"));
         let dark = write_theme(&td, "theme_dark", include_str!("testdata/theme_dark"));
-        let arg = format!("--theme=light:{light},dark:{dark}");
+        let arg = format!(
+            "--theme=light:{},dark:{}",
+            pair_value(&light),
+            pair_value(&dark)
+        );
 
         // Light
         {

crates/ghostty-config/src/file_load.rs

@@ -211,7 +211,15 @@ mod tests {
             open(&e("/nonexistent/ghostty/file")).unwrap_err(),
             OpenFileError::FileNotFound
         );
-        assert_eq!(open(&e("/tmp")).unwrap_err(), OpenFileError::NotAFile);
+        // Windows opens a directory with `ERROR_ACCESS_DENIED` (Zig 0.15's
+        // `OpenFile` maps FILE_IS_A_DIRECTORY to AccessDenied as well), which
+        // is an "unexpected" open error there.
+        let dir_err = if cfg!(windows) {
+            OpenFileError::FileOpenFailed
+        } else {
+            OpenFileError::NotAFile
+        };
+        assert_eq!(open(&e("/tmp")).unwrap_err(), dir_err);
         let p = std::env::temp_dir().join(format!("ghostty-file-load-{}", std::process::id()));
         std::fs::write(&p, "").unwrap();
         assert_eq!(

crates/ghostty-config/src/path.rs

@@ -158,7 +158,7 @@ impl Path {
         std::fs::read_dir(&base_path)?;
 
         let full = base_path.join(path.to_syscall_path()?);
-        let abs = match std::fs::canonicalize(&full) {
+        let abs = match realpath(&full) {
             Ok(p) => EncodedOs::from_path(&p),
             Err(err) if err.kind() == std::io::ErrorKind::NotFound => {
                 // The file doesn't exist. Try to resolve the relative path
@@ -276,6 +276,18 @@ impl ConfigField for RepeatablePath {
     }
 }
 
+/// `posix.realpath`: the canonical path without the `\\?\` verbatim prefix
+/// `std::fs::canonicalize` adds on Windows (Zig's `realpath` has none).
+#[cfg(windows)]
+pub(crate) fn realpath(path: impl AsRef<std::path::Path>) -> std::io::Result<std::path::PathBuf> {
+    ghostty_os::path::realpath(path)
+}
+
+#[cfg(not(windows))]
+pub(crate) fn realpath(path: impl AsRef<std::path::Path>) -> std::io::Result<std::path::PathBuf> {
+    std::fs::canonicalize(path)
+}
+
 #[cfg(test)]
 #[allow(clippy::unwrap_used)]
 mod tests {
@@ -391,7 +403,14 @@ mod tests {
         let mut diags = DiagnosticList::default();
         let mut p = Path::Required(e("../nope/x.conf"));
         p.expand(&e("/tmp"), &mut diags).unwrap();
-        assert_eq!(p, Path::Required(e("/nope/x.conf")));
+        // Resolved lexically with the platform's separator (`\nope\x.conf`
+        // on Windows, like Zig's `std.fs.path.resolve`).
+        let expected = if cfg!(windows) {
+            "\\nope\\x.conf"
+        } else {
+            "/nope/x.conf"
+        };
+        assert_eq!(p, Path::Required(e(expected)));
 
         let mut p = Path::Optional(e("/abs/path"));
         p.expand(&e("/tmp"), &mut diags).unwrap();
@@ -403,7 +422,7 @@ mod tests {
     #[test]
     fn expand_interior_nul_resolves_the_c_string_prefix_like_zig() {
         let tmp = ghostty_os::TempDir::init().unwrap();
-        let base = std::fs::canonicalize(tmp.path()).unwrap();
+        let base = realpath(tmp.path()).unwrap();
         std::fs::write(base.join("exists"), b"x").unwrap();
 
         // The syscall sees only the prefix, which exists: the real path of
@@ -429,7 +448,7 @@ mod tests {
     fn expand_symlink_to_non_utf8_target_round_trips() {
         use std::os::unix::ffi::OsStrExt;
         let tmp = ghostty_os::TempDir::init().unwrap();
-        let base = std::fs::canonicalize(tmp.path()).unwrap();
+        let base = realpath(tmp.path()).unwrap();
         let target = base.join(std::ffi::OsStr::from_bytes(b"t\xffarget"));
         std::fs::write(&target, b"x").unwrap();
         std::os::unix::fs::symlink(&target, base.join("link")).unwrap();

crates/ghostty-config/src/theme.rs

@@ -381,9 +381,14 @@ mod tests {
         );
         let mut d = DiagnosticList::default();
         assert!(open(&e("/tmp"), None, &mut d).is_none());
+        // Windows cannot open a directory as a file (AccessDenied).
         assert_eq!(
             d.items()[0].message,
-            "not reading theme from \"/tmp\": it is a directory"
+            if cfg!(windows) {
+                "failed to load theme from the path \"/tmp\": error.AccessDenied"
+            } else {
+                "not reading theme from \"/tmp\": it is a directory"
+            }
         );
     }
 
@@ -469,7 +474,11 @@ mod tests {
             let mut d = DiagnosticList::default();
             assert!(open(&e(name), Some(&EncodedOs::from_path(&dir)), &mut d).is_none());
             assert!(
-                d.items()[0].message.ends_with("it is a directory"),
+                d.items()[0].message.ends_with(if cfg!(windows) {
+                    "error.AccessDenied"
+                } else {
+                    "it is a directory"
+                }),
                 "{}",
                 d.items()[0].message
             );
@@ -484,7 +493,10 @@ mod tests {
         std::fs::write(dir.join("themes/mytheme-zzz"), "background = #000000\n").unwrap();
         let mut d = DiagnosticList::default();
         let t = open(&e("mytheme-zzz"), Some(&EncodedOs::from_path(&dir)), &mut d).unwrap();
-        assert!(t.path.ends_with_plain("themes/mytheme-zzz"));
+        assert!(
+            t.path
+                .ends_with_plain(&format!("themes{}mytheme-zzz", std::path::MAIN_SEPARATOR))
+        );
         assert!(d.is_empty());
         std::fs::remove_dir_all(&dir).unwrap();
     }
@@ -493,7 +505,13 @@ mod tests {
     fn theme_not_found_lists_tried_paths() {
         let mut d = DiagnosticList::default();
         assert!(open(&e("nope-zzz"), Some(&e("/nonexistent-res")), &mut d).is_none());
-        assert!(d.items().iter().any(|x| x.message
-            == "theme \"nope-zzz\" not found, tried path \"/nonexistent-res/themes/nope-zzz\""));
+        let tried = std::path::Path::new("/nonexistent-res")
+            .join("themes")
+            .join("nope-zzz");
+        let want = format!(
+            "theme \"nope-zzz\" not found, tried path \"{}\"",
+            tried.display()
+        );
+        assert!(d.items().iter().any(|x| x.message == want));
     }
 }