From 95a769eedc44bcfb33a18e95b9c61b49e41bfd61 Mon Sep 17 00:00:00 2001
From: Eduardo Soares <edurbs@gmail.com>
Date: Mon, 12 Oct 2026 22:55:19 -0300
Subject: [PATCH] Open: opening an already-open file focuses its tab (#1620)

Co-authored-by: GLM <noreply@z.ai>
---
 crates/ui-egui/src/last_session.rs |  2 +-
 crates/ui-egui/src/lib.rs          | 16 ++++++++++++++++
 crates/ui-egui/tests/editing.rs    | 30 ++++++++++++++++++++++++++++++
 3 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/crates/ui-egui/src/last_session.rs b/crates/ui-egui/src/last_session.rs
index bf64ea7ab..7bc4833c0 100644
--- a/crates/ui-egui/src/last_session.rs
+++ b/crates/ui-egui/src/last_session.rs
@@ -52,7 +52,7 @@ impl LastSession {
 /// `path` made absolute against the current directory, without resolving links (and without
 /// Windows' `\\?\` prefix, which `canonicalize` adds).
 #[cfg(not(target_arch = "wasm32"))]
-fn absolute(path: &str) -> String {
+pub(crate) fn absolute(path: &str) -> String {
     std::path::absolute(path).map_or_else(|_| path.to_string(), |p| p.to_string_lossy().into_owned())
 }
 
diff --git a/crates/ui-egui/src/lib.rs b/crates/ui-egui/src/lib.rs
index 91d534802..f34fd63de 100644
--- a/crates/ui-egui/src/lib.rs
+++ b/crates/ui-egui/src/lib.rs
@@ -1208,8 +1208,24 @@ impl PdfCraftApp {
         }
     }
 
+    /// The tab already showing the file at `path`, if any: its position in `views`. Paths are
+    /// compared after `absolute` normalization, so another spelling of the same file matches
+    /// (#1620).
+    #[cfg(not(target_arch = "wasm32"))]
+    fn view_showing(&self, path: &str) -> Option<usize> {
+        let path = crate::last_session::absolute(path);
+        self.views
+            .iter()
+            .position(|v| self.session.get(v.id).and_then(|d| d.path.as_deref()).map(crate::last_session::absolute).as_deref() == Some(path.as_str()))
+    }
+
     #[cfg(not(target_arch = "wasm32"))]
     pub fn open_path(&mut self, path: &str) {
+        if let Some(i) = self.view_showing(path) {
+            self.startup_superseded = true;
+            self.active = Some(i);
+            return;
+        }
         let name = std::path::Path::new(path).file_name().map(|n| n.to_string_lossy().into_owned()).unwrap_or_else(|| path.to_string());
         match std::fs::read(path) {
             Ok(bytes) => {
diff --git a/crates/ui-egui/tests/editing.rs b/crates/ui-egui/tests/editing.rs
index 17990d2fb..6a177831d 100644
--- a/crates/ui-egui/tests/editing.rs
+++ b/crates/ui-egui/tests/editing.rs
@@ -653,6 +653,36 @@ fn the_last_session_is_off_by_default_and_skips_missing_and_duplicate_files() {
     assert!(later.views.is_empty(), "neither opens from the session");
 }
 
+#[test]
+fn opening_the_same_path_again_focuses_its_tab() {
+    let pdfs = TempPdfs::new("dedup-open");
+    let a = pdfs.file("a.pdf", 1);
+    let b = pdfs.file("b.pdf", 1);
+    let mut h = session_harness(|_| {});
+    h.state_mut().open_path(&a);
+    h.state_mut().open_path(&b);
+    h.run_steps(2);
+    assert_eq!(h.state().views.len(), 2, "two different files open two tabs");
+    h.state_mut().open_path(&a);
+    h.run_steps(2);
+    assert_eq!(h.state().views.len(), 2, "opening an open file again adds no tab");
+    assert_eq!(h.state().active, Some(0), "the existing tab comes to the front");
+    assert_eq!(open_paths(h.state()), vec![a, b], "the tab order is untouched");
+}
+
+#[test]
+fn opening_the_same_file_with_a_dot_component_focuses_its_tab() {
+    let pdfs = TempPdfs::new("dedup-dot");
+    let a = pdfs.file("a.pdf", 1);
+    let dotted = format!("{}/./a.pdf", pdfs.0.display());
+    let mut h = session_harness(|_| {});
+    h.state_mut().open_path(&a);
+    h.state_mut().open_path(&dotted);
+    h.run_steps(2);
+    assert_eq!(h.state().views.len(), 1, "another spelling of the same file matches");
+    assert_eq!(h.state().active, Some(0));
+}
+
 #[test]
 fn save_prompt_stays_inside_the_screen_for_a_long_filename() {
     // Issue #161: an unwrapped title carrying a long filename widened the centered modal past