From 5f3b502ee769d1dc6206dd7ae5b77f0b160b6e6b Mon Sep 17 00:00:00 2001
From: Cam Saul <github@camsaul.com>
Date: Wed, 21 Aug 2024 22:48:25 +0000
Subject: [PATCH] Fix formatting when requires have metadata

---
 cljfmt/src/cljfmt/core.cljc       | 37 +++++++++++++++++++++++++++++--
 cljfmt/test/cljfmt/core_test.cljc | 27 ++++++++++++++++++++++
 2 files changed, 62 insertions(+), 2 deletions(-)

diff --git a/cljfmt/src/cljfmt/core.cljc b/cljfmt/src/cljfmt/core.cljc
index 561a1a4..1ebf050 100644
--- a/cljfmt/src/cljfmt/core.cljc
+++ b/cljfmt/src/cljfmt/core.cljc
@@ -568,10 +568,43 @@
 #?(:clj
    (defn- as-zloc->alias-mapping [as-zloc]
      (let [alias             (some-> as-zloc z/right z/sexpr)
-           current-namespace (some-> as-zloc z/leftmost z/sexpr)
+           ;; `leftmost` might be an `uneval` node e.g. in
+           ;;
+           ;;    [#_{:clj-kondo/ignore [:x]} a.namespace :as n]
+           ;;
+           ;; so look for the first symbol node. The token can also have
+           ;; metadata on it e.g.
+           ;;
+           ;;    [^{:clj-kondo/ignore [:x]} a.namespace :as n]
+           ;;
+           ;; which is why we need to `skip-meta` in find.
+           current-namespace (some-> as-zloc
+                                     z/leftmost
+                                     (z/find #(n/symbol-node?
+                                               (z/node (skip-meta %))))
+                                     z/sexpr)
            grandparent-node  (some-> as-zloc z/up z/up)
+           ;; For something like
+           ;;
+           ;;    [a [namespace :as n]]
+           ;;
+           ;; `grandparent-node` points to [a [namespace :as n]]. In this case
+           ;; `a` is the parent namespace.
+           ;;
+           ;; But for something like
+           ;;
+           ;;    ^{:x true} [a.namespace :as n]
+           ;;
+           ;; `grandparent-node` points to a `:meta` node e.g.
+           ;;
+           ;;    [<meta: ^{:x true} [a.namespace :as n]> ...]
+           ;;
+           ;; so make sure we're only looking at actual prefix forms like the
+           ;; former by checking whether it's a list or vector
            parent-namespace  (when-not (ns-require-form? grandparent-node)
-                               (first (z/child-sexprs grandparent-node)))]
+                               (when (or (z/vector? grandparent-node)
+                                         (z/list? grandparent-node))
+                                 (first (z/child-sexprs grandparent-node))))]
        (when (and (symbol? alias) (symbol? current-namespace))
          {(str alias) (if parent-namespace
                         (format "%s.%s" parent-namespace current-namespace)
diff --git a/cljfmt/test/cljfmt/core_test.cljc b/cljfmt/test/cljfmt/core_test.cljc
index a4c98f7..6827bbe 100644
--- a/cljfmt/test/cljfmt/core_test.cljc
+++ b/cljfmt/test/cljfmt/core_test.cljc
@@ -257,6 +257,33 @@
          {:indents {'thing.core/defn [[:inner 0]]}
           #?@(:cljs [:alias-map {"t" "thing.core"}])})
         "applies custom indentation to namespaced defn")
+    (testing "handles metadata on or comments before forms inside ns :require list"
+      (doseq [ignore-str [""
+                          "^{:clj-kondo/ignore [:discouraged-namespace]} "
+                          "^:clj-kondo/ignore "
+                          "^{some-symbol another-symbol} "
+                          "#_{:clj-kondo/ignore [:discouraged-namespace]} "
+                          "#_:clj-kondo/ignore "
+                          "^tag "
+                          "#_old-thing "]
+              ns-vec-str [(str ignore-str "[thing.core :as t]")
+                          (str ignore-str "[thing [core :as t]]")
+                          (str ignore-str "(thing [core :as t])")
+                          (str "[" ignore-str "thing.core :as t]")
+                          (str ignore-str " [" ignore-str "thing.core :as t]")]
+              :let [ns-str (str "(ns example (:require " ns-vec-str "))")]]
+        (testing ns-str
+          (is (reformats-to?
+               [ns-str
+                ""
+                "(t/defn foo [x]"
+                "(+ x 1))"]
+               [ns-str
+                ""
+                "(t/defn foo [x]"
+                "  (+ x 1))"]
+               {:indents {'ns [[:block 1]], 'thing.core/defn [[:inner 0]]}
+                #?@(:cljs [:alias-map {"t" "thing.core"}])})))))
     (is (reformats-to?
          ["(comment)"
           "(ns thing.core)"