add go to definition feature for extends/include tags (#274)

Author: joshuadavidthomas

Cargo.lock

@@ -36,6 +36,7 @@ tracing = "0.1"
 tracing-appender = "0.2"
 tracing-subscriber = { version = "0.3", features = ["env-filter", "fmt", "time"] }
 url = "2.5"
+walkdir = "2.5"
 which = "8.0"
 
 # testing

Cargo.toml

@@ -73,4 +73,8 @@ impl SemanticDb for Db {
     fn tag_index(&self) -> TagIndex<'_> {
         TagIndex::from_specs(self)
     }
+
+    fn template_dirs(&self) -> Option<Vec<Utf8PathBuf>> {
+        None
+    }
 }

crates/djls-bench/src/db.rs

@@ -12,6 +12,7 @@ djls-workspace = { workspace = true }
 
 salsa = { workspace = true }
 tower-lsp-server = { workspace = true }
+tracing = { workspace = true }
 
 [lints]
 workspace = true

crates/djls-ide/Cargo.toml

@@ -1,9 +1,11 @@
 mod completions;
 mod diagnostics;
+mod navigation;
 mod snippets;
 
 pub use completions::handle_completion;
 pub use diagnostics::collect_diagnostics;
+pub use navigation::goto_template_definition;
 pub use snippets::generate_partial_snippet;
 pub use snippets::generate_snippet_for_tag;
 pub use snippets::generate_snippet_for_tag_with_end;

crates/djls-ide/src/lib.rs

@@ -0,0 +1,69 @@
+use djls_semantic::resolve_template;
+use djls_semantic::ResolveResult;
+use djls_source::File;
+use djls_source::LineCol;
+use djls_source::Offset;
+use djls_source::PositionEncoding;
+use djls_templates::parse_template;
+use djls_templates::Node;
+use tower_lsp_server::lsp_types;
+use tower_lsp_server::UriExt;
+
+pub fn goto_template_definition(
+    db: &dyn djls_semantic::Db,
+    file: File,
+    position: lsp_types::Position,
+    encoding: PositionEncoding,
+) -> Option<lsp_types::GotoDefinitionResponse> {
+    let nodelist = parse_template(db, file)?;
+
+    let line_index = file.line_index(db);
+    let source = file.source(db);
+    let line_col = LineCol::new(position.line, position.character);
+
+    let offset = encoding.line_col_to_offset(line_index, line_col, source.as_str())?;
+
+    let template_name = find_template_name_at_offset(nodelist.nodelist(db), offset)?;
+    tracing::debug!("Found template reference: '{}'", template_name);
+
+    match resolve_template(db, &template_name) {
+        ResolveResult::Found(template) => {
+            let path = template.path_buf(db);
+            tracing::debug!("Resolved template to: {}", path);
+            let uri = lsp_types::Uri::from_file_path(path.as_std_path())?;
+
+            Some(lsp_types::GotoDefinitionResponse::Scalar(
+                lsp_types::Location {
+                    uri,
+                    range: lsp_types::Range::default(),
+                },
+            ))
+        }
+        ResolveResult::NotFound { tried, .. } => {
+            tracing::warn!("Template '{}' not found. Tried: {:?}", template_name, tried);
+            None
+        }
+    }
+}
+
+fn find_template_name_at_offset(nodes: &[Node], offset: Offset) -> Option<String> {
+    for node in nodes {
+        if let Node::Tag {
+            name, bits, span, ..
+        } = node
+        {
+            if (name == "extends" || name == "include") && span.contains(offset) {
+                let template_str = bits.first()?;
+                let template_name = template_str
+                    .trim()
+                    .trim_start_matches('"')
+                    .trim_end_matches('"')
+                    .trim_start_matches('\'')
+                    .trim_end_matches('\'')
+                    .to_string();
+                return Some(template_name);
+            }
+        }
+    }
+    None
+}

crates/djls-ide/src/navigation.rs

@@ -10,13 +10,15 @@
     from queries import QueryData
     from queries import get_installed_templatetags
     from queries import get_python_environment_info
+    from queries import get_template_dirs
     from queries import initialize_django
 except ImportError:
     # Fall back to relative import (when running with python -m)
     from .queries import Query
     from .queries import QueryData
     from .queries import get_installed_templatetags
     from .queries import get_python_environment_info
+    from .queries import get_template_dirs
     from .queries import initialize_django
 
 
@@ -40,11 +42,19 @@ def to_dict(self) -> dict[str, Any]:
                 data_dict = asdict(self.data)
                 # Convert Path objects to strings
                 for key, value in data_dict.items():
-                    if key in ["sys_base_prefix", "sys_executable", "sys_prefix"]:
-                        if value:
-                            data_dict[key] = str(value)
-                    elif key == "sys_path":
+                    # Handle single Path objects
+                    if hasattr(value, "__fspath__"):  # Path-like object
+                        data_dict[key] = str(value)
+                    # Handle lists of Path objects
+                    elif (
+                        isinstance(value, list)
+                        and value
+                        and hasattr(value[0], "__fspath__")
+                    ):
                         data_dict[key] = [str(p) for p in value]
+                    # Handle optional Path objects (could be None)
+                    elif value is None:
+                        pass  # Keep None as is
                 d["data"] = data_dict
         return d
 
@@ -62,16 +72,19 @@ def handle_request(request: dict[str, Any]) -> DjlsResponse:
 
         args = request.get("args")
 
-        if query == Query.PYTHON_ENV:
+        if query == Query.DJANGO_INIT:
+            success, error = initialize_django()
+            return DjlsResponse(ok=success, data=None, error=error)
+
+        elif query == Query.PYTHON_ENV:
             return DjlsResponse(ok=True, data=get_python_environment_info())
 
+        elif query == Query.TEMPLATE_DIRS:
+            return DjlsResponse(ok=True, data=get_template_dirs())
+
         elif query == Query.TEMPLATETAGS:
             return DjlsResponse(ok=True, data=get_installed_templatetags())
 
-        elif query == Query.DJANGO_INIT:
-            success, error = initialize_django()
-            return DjlsResponse(ok=success, data=None, error=error)
-
         return DjlsResponse(ok=False, error=f"Unhandled query type: {query}")
 
     except Exception as e:

crates/djls-project/inspector/inspector.py

@@ -9,9 +9,27 @@
 
 
 class Query(str, Enum):
+    DJANGO_INIT = "django_init"
     PYTHON_ENV = "python_env"
+    TEMPLATE_DIRS = "template_dirs"
     TEMPLATETAGS = "templatetags"
-    DJANGO_INIT = "django_init"
+
+
+def initialize_django() -> tuple[bool, str | None]:
+    import django
+    from django.apps import apps
+
+    try:
+        if not os.environ.get("DJANGO_SETTINGS_MODULE"):
+            return False, None
+
+        if not apps.ready:
+            django.setup()
+
+        return True, None
+
+    except Exception as e:
+        return False, str(e)
 
 
 @dataclass
@@ -43,21 +61,30 @@ def get_python_environment_info():
     )
 
 
-def initialize_django() -> tuple[bool, str | None]:
-    import django
+@dataclass
+class TemplateDirsQueryData:
+    dirs: list[Path]
+
+
+def get_template_dirs() -> TemplateDirsQueryData:
     from django.apps import apps
+    from django.conf import settings
 
-    try:
-        if not os.environ.get("DJANGO_SETTINGS_MODULE"):
-            return False, None
+    dirs = []
 
-        if not apps.ready:
-            django.setup()
+    for engine in settings.TEMPLATES:
+        if "django" not in engine["BACKEND"].lower():
+            continue
 
-        return True, None
+        dirs.extend(engine.get("DIRS", []))
 
-    except Exception as e:
-        return False, str(e)
+        if engine.get("APP_DIRS", False):
+            for app_config in apps.get_app_configs():
+                template_dir = Path(app_config.path) / "templates"
+                if template_dir.exists():
+                    dirs.append(template_dir)
+
+    return TemplateDirsQueryData(dirs)
 
 
 @dataclass
@@ -108,4 +135,4 @@ def get_installed_templatetags() -> TemplateTagQueryData:
     return TemplateTagQueryData(templatetags=templatetags)
 
 
-QueryData = PythonEnvironmentQueryData | TemplateTagQueryData
+QueryData = PythonEnvironmentQueryData | TemplateDirsQueryData | TemplateTagQueryData

crates/djls-project/inspector/queries.py

@@ -1,5 +1,6 @@
 use std::ops::Deref;
 
+use camino::Utf8PathBuf;
 use serde::Deserialize;
 use serde::Serialize;
 
@@ -28,6 +29,50 @@ pub fn django_available(db: &dyn ProjectDb, _project: Project) -> bool {
     inspector::query(db, &DjangoInitRequest).is_some()
 }
 
+#[derive(Serialize)]
+struct TemplateDirsRequest;
+
+#[derive(Deserialize)]
+struct TemplateDirsResponse {
+    dirs: Vec<Utf8PathBuf>,
+}
+
+impl InspectorRequest for TemplateDirsRequest {
+    const NAME: &'static str = "template_dirs";
+    type Response = TemplateDirsResponse;
+}
+
+#[salsa::tracked]
+pub fn template_dirs(db: &dyn ProjectDb, _project: Project) -> Option<TemplateDirs> {
+    tracing::debug!("Requesting template directories from inspector");
+
+    let response = inspector::query(db, &TemplateDirsRequest)?;
+
+    let dir_count = response.dirs.len();
+    tracing::info!(
+        "Retrieved {} template directories from inspector",
+        dir_count
+    );
+
+    for (i, dir) in response.dirs.iter().enumerate() {
+        tracing::debug!("  Template dir [{}]: {}", i, dir);
+    }
+
+    let missing_dirs: Vec<_> = response.dirs.iter().filter(|dir| !dir.exists()).collect();
+
+    if !missing_dirs.is_empty() {
+        tracing::warn!(
+            "Found {} non-existent template directories: {:?}",
+            missing_dirs.len(),
+            missing_dirs
+        );
+    }
+
+    Some(response.dirs)
+}
+
+type TemplateDirs = Vec<Utf8PathBuf>;
+
 #[derive(Serialize)]
 struct TemplatetagsRequest;
 

crates/djls-project/src/django.rs

@@ -6,6 +6,7 @@ mod python;
 
 pub use db::Db;
 pub use django::django_available;
+pub use django::template_dirs;
 pub use django::templatetags;
 pub use django::TemplateTags;
 pub use inspector::Inspector;