[Fix #3754] Fix regex in cider-ns-from-p.

CHANGELOG.md

@@ -3,7 +3,7 @@
 ## master (unreleased)
 
 ### Changes
-
+- [#3754](https://github.com/clojure-emacs/cider/issues/3754): Fix regex in `cider-ns-from-p`.
 - [#3753](https://github.com/clojure-emacs/cider/pull/3753): Add `cider-log-show-frameworks` command to show available log frameworks in a buffer.
 - [#3746](https://github.com/clojure-emacs/cider/issues/3746): Bring back `cider` completion style for activating backend-driven completion.
 

cider-client.el

@@ -108,7 +108,7 @@ EVAL-BUFFER is the buffer where the spinner was started."
 ;;; Evaluation helpers
 (defun cider-ns-form-p (form)
   "Check if FORM is an ns form."
-  (string-match-p "^[[:space:]]*\(ns\\([[:space:]]*$\\|[[:space:]]+\\)" form))
+  (string-match-p "\\`[[:space:]]*\(ns\\([[:space:]]*$\\|[[:space:]]+\\)" form))
 
 (defun cider-ns-from-form (ns-form)
   "Get ns substring from NS-FORM."

test/cider-client-tests.el

@@ -132,6 +132,17 @@
     (expect (cider-ensure-op-supported "foo")
             :to-throw 'user-error)))
 
+(describe "cider-ns-form-p"
+  (it "doesn't match ns in a string"
+      (let ((ns-in-string "\"\n(ns bar)\n\""))
+        (expect (cider-ns-form-p ns-in-string) :to-equal nil)))
+  (it "matches ns"
+      (let ((ns "(ns bar)\n"))
+        (expect (cider-ns-form-p ns) :to-equal 0)))
+  (it "matches ns with leading spaces"
+      (let ((ns "  (ns bar)\n"))
+        (expect (cider-ns-form-p ns) :to-equal 0))))
+
 (describe "cider-expected-ns"
   (before-each
     (spy-on 'cider-connected-p :and-return-value t)