T18 round 2 fixes: a folder the terminal cannot enter stops the start, and links read combining clusters whole

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Cargo.lock

@@ -1600,6 +1600,7 @@ dependencies = [
  "raw-window-handle",
  "regex",
  "rust-embed",
+ "rustix 1.1.5",
  "serde",
  "serde_json",
  "smallvec",

Cargo.toml

@@ -39,6 +39,9 @@ cocoa = "0.26"
 objc = "0.2"
 raw-window-handle = "0.6"
 
+[target.'cfg(unix)'.dependencies]
+rustix = { version = "1", default-features = false, features = ["std", "fs"] }
+
 [dev-dependencies]
 env_logger = "0.11"
 

TASKS.md

@@ -240,4 +240,5 @@ Per-component lines live in `tasks/`. Tags there:
 | T17d | 2 | PASS | |
 | T17e | 1 | PASS | |
 | T18 | 1 | FAIL | a missing folder ran in the app's own; combining marks dropped; Tab skipped the terminal; its wheel scrolled the page too; clear kept find matches; New bash reused the old shell; the dark script typed into the replay |
-| T18 | 2 | — | pending review |
+| T18 | 2 | FAIL | a folder it could not enter still started the shell elsewhere; links read cluster cells as spaces |
+| T18 | 3 | — | pending review |

src/terminal/frame.rs

@@ -49,19 +49,24 @@ pub(crate) struct Frame {
     pub cursor: Option<(usize, usize, CursorShape)>,
 }
 
+impl Row {
+    /// Each cell's text, a combining cluster whole.
+    pub(crate) fn cells(&self) -> Vec<String> {
+        let mut cells: Vec<String> = self.text.chars().map(String::from).collect();
+        for (column, cluster, _) in &self.clusters {
+            cells[*column] = cluster.clone();
+        }
+        cells
+    }
+}
+
 impl Frame {
     /// The screen's text, trailing spaces gone.
     pub(crate) fn text(&self) -> String {
         let lines: Vec<String> = self
             .rows
             .iter()
-            .map(|row| {
-                let mut cells: Vec<String> = row.text.chars().map(String::from).collect();
-                for (column, cluster, _) in &row.clusters {
-                    cells[*column] = cluster.clone();
-                }
-                cells.concat().trim_end().to_string()
-            })
+            .map(|row| row.cells().concat().trim_end().to_string())
             .collect();
         lines.join("\n").trim_end().to_string()
     }

src/terminal/input.rs

@@ -144,11 +144,26 @@ impl Terminal {
     }
 
     /// The link a row shows at `column`: its columns and target.
-    fn link_at(&self, row: usize, column: usize) -> Option<(usize, Range<usize>, Target)> {
-        let text = &self.shown.rows.get(row)?.text;
-        links(text).into_iter().find_map(|(bytes, target)| {
-            let start = text[..bytes.start].chars().count();
-            let end = start + text[bytes].chars().count();
+    pub(crate) fn link_at(
+        &self,
+        row: usize,
+        column: usize,
+    ) -> Option<(usize, Range<usize>, Target)> {
+        let cells = self.shown.rows.get(row)?.cells();
+        let text = cells.concat();
+        let column_of = |byte: usize| {
+            let mut from = 0;
+            cells
+                .iter()
+                .position(|cell| {
+                    let past = from >= byte;
+                    from += cell.len();
+                    past
+                })
+                .unwrap_or(cells.len())
+        };
+        links(&text).into_iter().find_map(|(bytes, target)| {
+            let (start, end) = (column_of(bytes.start), column_of(bytes.end));
             (start..end)
                 .contains(&column)
                 .then_some((row, start..end, target))

src/terminal/pty.rs

@@ -55,6 +55,10 @@ pub(crate) fn spawn(launch: &Launch, size: TermSize, cell: (u16, u16)) -> anyhow
             "a terminal cannot start in {}: no such folder",
             cwd.display()
         );
+        #[cfg(unix)]
+        rustix::fs::access(cwd, rustix::fs::Access::EXEC_OK).map_err(|error| {
+            anyhow::anyhow!("a terminal cannot enter {}: {error}", cwd.display())
+        })?;
     }
     let (sender, events) = unbounded();
     let listener = Listener(sender);
@@ -110,6 +114,26 @@ mod tests {
 
     use super::*;
 
+    #[test]
+    fn a_folder_that_cannot_be_entered_stops_the_start() {
+        use std::os::unix::fs::PermissionsExt;
+        let folder = std::env::temp_dir().join(format!("ely-shut-{}", std::process::id()));
+        std::fs::create_dir_all(&folder).expect("a temp folder");
+        std::fs::set_permissions(&folder, std::fs::Permissions::from_mode(0o600))
+            .expect("mode 600");
+        let launch = Launch {
+            program: Some(("/bin/sh".into(), vec!["-c".into(), "true".into()])),
+            cwd: Some(folder.clone()),
+            ..Launch::default()
+        };
+        let started = spawn(&launch, TermSize::new(20, 4), (8, 16));
+        std::fs::set_permissions(&folder, std::fs::Permissions::from_mode(0o700))
+            .expect("mode 700");
+        std::fs::remove_dir(&folder).expect("the temp folder goes");
+        let error = started.err().expect("a folder it cannot enter is an error");
+        assert!(error.to_string().contains("ely-shut"));
+    }
+
     #[test]
     fn a_missing_folder_stops_the_start() {
         let launch = Launch {

src/terminal/tests.rs

@@ -1,6 +1,6 @@
 use gpui::{Entity, TestAppContext, VisualTestContext};
 
-use super::Terminal;
+use super::{Target, Terminal};
 use crate::{editor::FindOptions, theme::Theme};
 
 fn replayed<'a>(
@@ -69,3 +69,13 @@ fn clearing_drops_the_matches(cx: &mut TestAppContext) {
         assert_eq!(terminal.matches(), (0, None));
     });
 }
+
+#[gpui::test]
+fn a_link_keeps_its_combining_marks(cx: &mut TestAppContext) {
+    let (terminal, cx) = replayed("a https://e.dev/cafe\u{301}/x".as_bytes(), cx);
+    terminal.read_with(cx, |terminal, _| {
+        let (_, columns, target) = terminal.link_at(0, 10).expect("a link under column 10");
+        assert_eq!(columns, 2..22);
+        assert_eq!(target, Target::Url("https://e.dev/cafe\u{301}/x".into()));
+    });
+}