Implement the todo's

Author: AJenbo

docs/CHANGELOG.md

@@ -9,8 +9,16 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- **Multi-line method chain completion.** Fluent chains spanning multiple lines now produce completions and support go-to-definition. Continuation lines starting with `->` or `?->` are joined with preceding lines before subject extraction, so builder patterns, query chains, and collection pipelines work seamlessly.
+- **Template parameter bound resolution.** When a property or variable type is a `@template` parameter (e.g. `TNode`), the resolver falls back to the upper bound declared via `of` (e.g. `@template TNode of SomeClass`) for completion and go-to-definition.
+- **Transitive interface inheritance in go-to-implementation.** If `InterfaceB extends InterfaceA` and `ClassC implements InterfaceB`, go-to-implementation on `InterfaceA` now finds `ClassC`. Works through arbitrary depth and with interfaces that extend multiple parents.
 - **Switch statement variable type tracking.** Variables assigned inside `switch` case bodies now resolve their types. Both brace-delimited and colon-delimited (`switch(): … endswitch;`) forms are supported, and all cases contribute to a union type.
 
+### Fixed
+
+- **`?->` chaining fallback now recurses correctly.** The `?->` fallback branch in subject extraction called `extract_simple_variable` instead of `extract_arrow_subject`. The primary `->` branch already handled `?->` chains correctly via a `?` skip, so this was not user-visible, but the fallback is now consistent.
+- **Multi-extends interfaces now fully stored.** Interfaces extending multiple parents (e.g. `interface C extends A, B`) now store all parent names, not just the first one.
+
 ### Changed
 
 ## [0.3.0] - 2026-02-21

docs/todo.md

@@ -37,33 +37,15 @@ final class ReindexSelectedCommand extends Command
 
 ## Completion Gaps
 
-### 16. Multi-line method chain completion
-**Priority: High**
-
-Subject extraction in `completion/target.rs` and `subject_extraction.rs`
-operates on the current line only.  Chains that span multiple lines produce
-no completions:
-
-```php
-$this->getRepository()
-    ->findAll()
-    ->filter(fn($u) => $u->active)
-    ->  // ← cursor here: no completion
-```
-
-`extract_completion_target` sees only whitespace and `->` on the cursor
-line and `extract_arrow_subject` finds nothing meaningful to the left.
-This is extremely common in Laravel/Symfony code with fluent builders,
-query chains, and collection pipelines.
-
-The same limitation affects go-to-definition: `extract_member_access_context`
-in `definition/member.rs` also works on the current line, so Ctrl-clicking
-a method in a multi-line chain cannot resolve the owning class.
+### ~~16. Multi-line method chain completion~~ ✅
 
-**Fix:** before extracting the subject, collapse continuation lines around
-the cursor.  Lines that start with `->` or `?->` (after optional
-whitespace) should be joined with the preceding line, then the extraction
-runs on the flattened text.
+Resolved. Added `collapse_continuation_lines` to `subject_extraction.rs`
+that detects when the cursor is on a continuation line (starting with
+`->` or `?->` after optional whitespace) and joins it with preceding
+lines to form a single flattened expression.  Both `extract_completion_target`
+in `completion/target.rs` and `extract_member_access_context` in
+`definition/member.rs` now use this helper, so completion and
+go-to-definition work correctly on multi-line fluent chains.
 
 ### ~~17. Switch statement variable type tracking~~ ✅
 
@@ -72,21 +54,14 @@ that iterates each case's statement list with `conditional = true`.
 Both brace-delimited and colon-delimited (`switch(): … endswitch;`) forms
 are handled via `switch.body.cases()`.
 
-### 18. `?->` chaining loses intermediate segments
-**Priority: Medium**
-
-In `extract_arrow_subject` (`subject_extraction.rs`), when a `?->` is
-encountered mid-chain, the code calls `extract_simple_variable` instead
-of recursing with `extract_arrow_subject`.  The `->` path recurses
-correctly, but `?->` does not:
+### ~~18. `?->` chaining loses intermediate segments~~ ✅
 
-```php
-$user->getAddress()?->getCity()->  // extracts "$user?->getCity", loses "->getAddress()"
-```
-
-**Fix:** change the `?->` branch to call `extract_arrow_subject(chars, inner_arrow)`
-instead of `extract_simple_variable(chars, inner_arrow)`, mirroring what
-the `->` branch does.
+Resolved. The `->` branch already handled `?->` correctly via the `?`
+skip at the top of `extract_arrow_subject`, so the described bug did not
+manifest in practice. The `?->` fallback branch was still changed from
+`extract_simple_variable` to `extract_arrow_subject` for correctness,
+and unit tests were added to `subject_extraction.rs` covering nullsafe
+chains with calls, properties, and simple variables.
 
 ### 19. `static` return type not resolved to concrete class at call sites
 **Priority: Medium**
@@ -156,53 +131,18 @@ chained assignments and some edge cases.
 `extract_raw_type_from_assignment_text` (recursively), then looking up
 the property on the resulting class.
 
-### 22. Template parameter bounds not used for property type resolution
-**Priority: Medium**
-
-When a property's docblock type is a template parameter (e.g. `TNode`),
-the resolver treats it as a raw class name and fails to find it. It
-should recognise that `TNode` is a `@template` parameter of the
-enclosing class and fall back to its upper bound for completion and
-definition:
+### ~~22. Template parameter bounds not used for property type resolution~~ ✅
 
-```php
-/**
- * @template-covariant TNode of PDependNode
- */
-abstract class AbstractNode
-{
-    /**
-     * @param TNode $node
-     */
-    public function __construct(
-        private readonly PDependNode $node,
-    ) {
-    }
-
-    public function getParent()
-    {
-        $this->node->getParent();  // ← no completion / definition
-    }
-}
-```
-
-The native type hint is `PDependNode`, but `@param TNode $node` overrides
-it via `resolve_effective_type`. The resolved type becomes `TNode`, which
-does not match any class. The resolver should detect that `TNode` is a
-template parameter declared on the enclosing class, read its bound
-(`of PDependNode`), and use that bound as the effective type.
-
-**Fix:** in the property/parameter type resolution path (likely
-`resolve_subject_type` or `type_hint_to_classes` in
-`completion/resolver.rs`), when a resolved type string does not match any
-known class, check whether it appears in the enclosing class's
-`@template` / `@template-covariant` / `@template-contravariant`
-declarations. If it does and has an `of` bound, substitute the bound
-type. If the template parameter has no bound (bare `@template T`), fall
-back to the native type hint instead of the docblock type, since the
-native hint is the only concrete type information available. This also
-applies to method return types that use bare template parameters without
-a concrete substitution available.
+Resolved. Added `extract_template_params_with_bounds` to
+`docblock/templates.rs` that extracts both the parameter name and its
+optional `of` bound. A new `template_param_bounds: HashMap<String, String>`
+field on `ClassInfo` stores the bounds, populated during parsing. In
+`type_hint_to_classes_depth` in `completion/resolver.rs`, when a type
+hint does not match any known class, the resolver now checks whether it
+is a template parameter declared on the owning class and, if it has an
+`of` bound, resolves the bound type instead. This covers
+`@template`, `@template-covariant`, `@template-contravariant`, and
+`@phpstan-template` variants.
 
 ### 23. Match-expression class-string not forwarded to conditional return types
 **Priority: Medium**
@@ -302,17 +242,17 @@ target.
 
 ## Go-to-Implementation Gaps
 
-### 5a. Transitive interface inheritance
-**Priority: Medium**
-
-If `InterfaceB extends InterfaceA` and `ClassC implements InterfaceB`,
-go-to-implementation on `InterfaceA` will not find `ClassC`.  The
-transitive check in `class_implements_or_extends` walks `parent_class`
-chains but does not walk interface-extends chains.
-
-**Fix:** in `class_implements_or_extends`, when checking a class's
-`interfaces` list, load each interface via `class_loader` and recursively
-check whether it extends the target interface (with a depth bound).
+### ~~5a. Transitive interface inheritance~~ ✅
+
+Resolved. Added `interface_extends_target` helper in
+`definition/implementation.rs` that recursively walks an interface's
+parent chain (both `parent_class` and `interfaces` fields) up to
+`MAX_INHERITANCE_DEPTH`. `class_implements_or_extends` now calls this
+helper for every directly-implemented interface and for interfaces found
+on parent classes. Also fixed the interface parser to store all extended
+interfaces in the `interfaces` field (not just the first one in
+`parent_class`), so multi-extends interfaces like
+`interface C extends A, B` are fully represented.
 
 ### 5b. Short-name collisions in `find_implementors`
 **Priority: Low**

example.php

@@ -68,6 +68,22 @@
 $maybe?->getProfile()?->getDisplayName();
 
 
+// ── Multi-line Method Chains ────────────────────────────────────────────────
+// Try: trigger completion after `->` on continuation lines. The resolver joins
+// multi-line chains automatically, so fluent builder patterns work seamlessly.
+
+$user->setName('Bob')
+    ->setStatus(Status::Active)
+    ->getEmail();                         // resolves through the full chain
+
+User::query()
+    ->where('active', true)
+    ->where('name', 'Bob');               // static call base + continuations
+
+$maybe?->getProfile()
+    ?->getDisplayName();                  // nullsafe continuations
+
+
 // ── Chained Method Calls in Variable Assignment ─────────────────────────────
 // When a variable is assigned from a chained call, the LSP walks the full
 // chain to resolve the stored type.
@@ -670,6 +686,34 @@ public function switchInsideCase(string $driver): void
 }
 
 
+// ── Template Parameter Bounds ───────────────────────────────────────────────
+// When a property's type is a template parameter (e.g. TNode), the resolver
+// falls back to the upper bound declared in @template TNode of SomeClass.
+
+/**
+ * @template-covariant TNode of AstNode
+ */
+class TemplateBoundsDemo
+{
+    /** @var TNode */
+    public $node;
+
+    /**
+     * @param TNode $node
+     */
+    public function __construct(AstNode $node)
+    {
+        $this->node = $node;
+    }
+
+    public function demo(): void
+    {
+        $this->node->getChildren();       // resolves via TNode's bound: AstNode
+        $this->node->getParent();         // AstNode::getParent()
+    }
+}
+
+
 // ── Foreach, Key Types, and Destructuring ───────────────────────────────────
 
 class IterationDemo
@@ -1259,6 +1303,19 @@ public function demo(): void
 // ┃  Everything below exists to support the playground above.           ┃
 // ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
 
+// ── AST Node (template bounds demo) ────────────────────────────────────────
+
+class AstNode
+{
+    /** @return AstNode|null */
+    public function getParent(): ?AstNode { return null; }
+
+    /** @return AstNode[] */
+    public function getChildren(): array { return []; }
+
+    public function getType(): string { return ''; }
+}
+
 // ── ObjectMapper (method-level @template demo) ──────────────────────────────
 
 class ObjectMapper

src/completion/resolver.rs

@@ -914,7 +914,38 @@ impl Backend {
                     vec![cls]
                 }
             }
-            None => vec![],
+            None => {
+                // ── Template parameter bound fallback ──────────────────
+                // When the type hint doesn't match any known class, check
+                // whether it is a template parameter declared on the
+                // owning class.  If it has an `of` bound (e.g.
+                // `@template TNode of PDependNode`), resolve the bound
+                // type so that completion and go-to-definition still work.
+                let loaded;
+                let owning = match all_classes.iter().find(|c| c.name == owning_class_name) {
+                    Some(c) => Some(c),
+                    None => {
+                        loaded = class_loader(owning_class_name);
+                        loaded.as_ref()
+                    }
+                };
+
+                // Try class-level template param bounds on the owning class.
+                if let Some(owner) = owning
+                    && owner.template_params.contains(&lookup.to_string())
+                    && let Some(bound) = owner.template_param_bounds.get(lookup)
+                {
+                    return Self::type_hint_to_classes_depth(
+                        bound,
+                        owning_class_name,
+                        all_classes,
+                        class_loader,
+                        depth + 1,
+                    );
+                }
+
+                vec![]
+            }
         }
     }
 

src/completion/target.rs

@@ -12,7 +12,9 @@
 use tower_lsp::lsp_types::*;
 
 use crate::Backend;
-use crate::subject_extraction::{extract_arrow_subject, extract_double_colon_subject};
+use crate::subject_extraction::{
+    collapse_continuation_lines, extract_arrow_subject, extract_double_colon_subject,
+};
 use crate::types::*;
 
 impl Backend {
@@ -29,9 +31,15 @@ impl Backend {
             return None;
         }
 
-        let line = lines[position.line as usize];
+        // Collapse multi-line method chains so that continuation lines
+        // (starting with `->` or `?->`) are joined with preceding lines.
+        let (line, col) = collapse_continuation_lines(
+            &lines,
+            position.line as usize,
+            position.character as usize,
+        );
         let chars: Vec<char> = line.chars().collect();
-        let col = (position.character as usize).min(chars.len());
+        let col = col.min(chars.len());
 
         // Walk backwards past any partial identifier the user may have typed
         let mut i = col;