Fix mod path when both mod file and mod dir exist

lua/neotest-rust/dap.lua

@@ -83,15 +83,18 @@ end
 -- Determine if mod is in <mod_name>.rs or <mod_name>/mod.rs
 local function construct_mod_path(src_path, mod_name)
     local match_str = "(.-)[^\\/]-%.?(%w+)%.?[^\\/]*$"
-    local abs_path, _ = string.match(src_path, match_str)
+    local abs_path, parent_mod = string.match(src_path, match_str)
 
     local mod_file = abs_path .. mod_name .. ".rs"
     local mod_dir = abs_path .. mod_name .. sep .. "mod.rs"
+    local child_mod = abs_path .. parent_mod .. sep .. mod_name .. ".rs"
 
     if util.file_exists(mod_file) then
         return mod_file
     elseif util.file_exists(mod_dir) then
         return mod_dir
+    elseif util.file_exists(child_mod) then
+        return child_mod
     end
 
     return nil

tests/dap_spec.lua

@@ -61,6 +61,13 @@ describe("get_test_binary", function()
             assert.equal(expected, actual)
         end)
 
+        async.it("returns the test binary for src/parent/child.rs", function()
+            local expected = main_actual
+            local actual = dap.get_test_binary(root, root .. "/src/parent/child.rs")
+
+            assert.equal(expected, actual)
+        end)
+
         async.it("returns the test binary for tests/test_it.rs", function()
             assert(test_it_actual)
             local expected = root .. "/target/debug/deps/test_it-"

tests/data/simple-package/src/main.rs

@@ -1,4 +1,5 @@
 mod mymod;
+mod parent;
 
 fn main() {
     println!("Hello, world!");

tests/data/simple-package/src/parent.rs

@@ -0,0 +1 @@
+pub mod child;

tests/data/simple-package/src/parent/child.rs

@@ -0,0 +1,7 @@
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn math() {
+        assert_eq!(1 + 1, 2);
+    }
+}

tests/init_spec.lua

@@ -26,23 +26,23 @@ describe("discover_positions", function()
                 id = vim.loop.cwd() .. "/tests/data/simple-package/src/main.rs",
                 name = "main.rs",
                 path = vim.loop.cwd() .. "/tests/data/simple-package/src/main.rs",
-                range = { 0, 0, 25, 0 },
+                range = { 0, 0, 26, 0 },
                 type = "file",
             },
             {
                 {
                     id = "tests",
                     name = "tests",
                     path = vim.loop.cwd() .. "/tests/data/simple-package/src/main.rs",
-                    range = { 7, 0, 24, 1 },
+                    range = { 8, 0, 25, 1 },
                     type = "namespace",
                 },
                 {
                     {
                         id = "tests::basic_math",
                         name = "basic_math",
                         path = vim.loop.cwd() .. "/tests/data/simple-package/src/main.rs",
-                        range = { 9, 4, 11, 5 },
+                        range = { 10, 4, 12, 5 },
                         type = "test",
                     },
                 },
@@ -51,7 +51,7 @@ describe("discover_positions", function()
                         id = "tests::failed_math",
                         name = "failed_math",
                         path = vim.loop.cwd() .. "/tests/data/simple-package/src/main.rs",
-                        range = { 14, 4, 16, 5 },
+                        range = { 15, 4, 17, 5 },
                         type = "test",
                     },
                 },
@@ -60,15 +60,15 @@ describe("discover_positions", function()
                         id = "tests::nested",
                         name = "nested",
                         path = vim.loop.cwd() .. "/tests/data/simple-package/src/main.rs",
-                        range = { 18, 4, 23, 5 },
+                        range = { 19, 4, 24, 5 },
                         type = "namespace",
                     },
                     {
                         {
                             id = "tests::nested::nested_math",
                             name = "nested_math",
                             path = vim.loop.cwd() .. "/tests/data/simple-package/src/main.rs",
-                            range = { 20, 8, 22, 9 },
+                            range = { 21, 8, 23, 9 },
                             type = "test",
                         },
                     },