From 69fcd63fad917517272a0f5cc841c17090e2fe9d Mon Sep 17 00:00:00 2001
From: XeroOl <xerool@protonmail.com>
Date: Tue, 30 Aug 2022 22:30:39 -0500
Subject: [PATCH] goto definition understands (let)

---
 README.md                             | 9 +++++----
 src/fennel-ls/language.fnl            | 4 ++++
 test/goto-definition-test.fnl         | 5 ++++-
 test/test-project/goto-definition.fnl | 2 ++
 4 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 0af689d..a6a94ee 100644
--- a/README.md
+++ b/README.md
@@ -20,7 +20,7 @@ Features / To Do List / Things I would enjoy patches for:
     - [X] table destructuring
     - [X] multisyms
     - [X] `.` special form (when called with constants)
-    - [ ] `do` special form
+    - [X] `do` and `let` special form
     - [X] `require` and cross-module definition lookups
     - [ ] goes to a.method on `(: a :method)` when triggered at `:method`
     - [X] expanded macros (a little bit)
@@ -33,15 +33,16 @@ Features / To Do List / Things I would enjoy patches for:
     - [ ] mutation on aliased tables (difficult)
 - [X] Reports compiler errors
 - [ ] Reports linting issues
-    - [ ] Brainstorm more linting patterns (I spent a couple minutes brainstorming these ideas, other ideas are welcome of course)
     - [ ] Unused locals
-    - [ ] Discarding results from pcall/xpcall/other functions.
+    - [ ] Discarding results from pcall/xpcall/other functions
     - [ ] `unpack` or `values` into an operator special
     - [ ] `do`/`values` with only one inner form
     - [ ] redundant `do` as the last/only item in a form that accepts a "body"
-    - [ ] Dead code. (I'm not sure what sort of things cause dead code)
+    - [ ] `var` forms that could be `local`
+    - [ ] Dead code (I'm not sure what sort of things cause dead code)
     - [ ] Unused fields (difficult)
     - [ ] unification in a `match` pattern (difficult)
+    - [ ] Brainstorm more linting patterns (I spent a couple minutes brainstorming these ideas, other ideas are welcome of course)
 - [ ] Completion Suggestions
     - [X] from globals
     - [ ] from current scope
diff --git a/src/fennel-ls/language.fnl b/src/fennel-ls/language.fnl
index b7f71f2..61ece67 100644
--- a/src/fennel-ls/language.fnl
+++ b/src/fennel-ls/language.fnl
@@ -12,6 +12,7 @@ the data provided by compiler.fnl."
 (local -require- (sym :require))
 (local -dot- (sym :.))
 (local -do- (sym :do))
+(local -let- (sym :let))
 
 (var search nil) ;; all of the search functions are mutually recursive
 
@@ -52,6 +53,9 @@ the data provided by compiler.fnl."
 
     ;; A do block returns the last form
     [-do- & body]
+    (search self file (. body (length body)) stack)
+
+    [-let- _binding & body]
     (search self file (. body (length body)) stack)))
 
 (set search
diff --git a/test/goto-definition-test.fnl b/test/goto-definition-test.fnl
index 4f2e7a1..c8b89cf 100644
--- a/test/goto-definition-test.fnl
+++ b/test/goto-definition-test.fnl
@@ -66,7 +66,10 @@
     (check :goto-definition.fnl 45 15 :goto-definition.fnl 40 7 40 13))
 
   (it "works directly on a require/include (require XXX))"
-     (check :goto-definition.fnl 1 5 :bar.fnl 0 0 0 2)))
+    (check :goto-definition.fnl 1 5 :bar.fnl 0 0 0 2))
+
+  (it "goes to the last form of `do` and `let`"
+    (check :goto-definition.fnl 47 13 :goto-definition.fnl 47 30 47 52)))
 
   ;; TODO
   ;; (it "can go to a function in another file imported via destructuring assignment") ;; WORKS, just needs a test case
diff --git a/test/test-project/goto-definition.fnl b/test/test-project/goto-definition.fnl
index 019568d..5078808 100644
--- a/test/test-project/goto-definition.fnl
+++ b/test/test-project/goto-definition.fnl
@@ -44,3 +44,5 @@
 (local mixed [{:key [5 {:foo shallow}]}])
 (local funny (. mixed 1 :key 2 :foo))
 (print funny.field)
+
+(local object (do (let [a 10] {:my-definition :here})))