Add dry_run parameter to file editing tools

src/clojure_mcp/tools/file_edit/pipeline.clj

@@ -23,6 +23,8 @@
 (s/def ::old-string string?)
 (s/def ::new-string string?)
 (s/def ::nrepl-client-atom (s/nilable #(instance? clojure.lang.Atom %)))
+
+(s/def ::dry-run (s/nilable #{"diff" "new-source"}))
 ;; Pipeline specific steps
 
 ;; Using check-file-modified from form-edit/pipeline instead
@@ -117,15 +119,16 @@
    - file-path: Path to the file to edit
    - old-string: String to replace
    - new-string: New string to insert
-   - nrepl-client-atom: Atom containing the nREPL client (optional)
-   - config: Optional tool configuration map
+   - dry-run: Optional string, either \"diff\" or \"new-source\" to skip actual file write
+   - config: Optional tool configuration map with :nrepl-client-atom
 
    Returns:
    - A context map with the result of the operation"
-  [file-path old-string new-string {:keys [nrepl-client-atom] :as config}]
+  [file-path old-string new-string dry_run {:keys [nrepl-client-atom] :as config}]
   (let [initial-ctx {::form-pipeline/file-path file-path
                      ::old-string old-string
                      ::new-string new-string
+                     ::dry-run dry_run
                      ::form-pipeline/nrepl-client-atom nrepl-client-atom
                      ::form-pipeline/config config}]
     ;; Pipeline for existing file edit
@@ -147,9 +150,14 @@
      format-clojure-content ;; Format Clojure files automatically
      form-pipeline/determine-file-type ;; This will mark as "update"
      form-pipeline/generate-diff ;; Generate diff between old and new
-     form-pipeline/save-file ;; Save the file
-     form-pipeline/update-file-timestamp ;; Update the timestamp after save
-     form-pipeline/highlight-form))) ;; Update the timestamp after save ;; Update the timestamp after save
+     ;; Skip file operations if dry-run is set
+     (fn [ctx]
+       (if (::dry-run ctx)
+         ctx
+         (-> ctx
+             form-pipeline/save-file
+             form-pipeline/update-file-timestamp
+             form-pipeline/highlight-form)))))) ;; Update the timestamp after save ;; Update the timestamp after save
 
 ;; Format result for tool consumption
 (defn format-result
@@ -159,17 +167,25 @@
    - ctx: The final context map from the pipeline
 
    Returns:
-   - A map with :error, :message, and :diff keys, and potentially :repaired"
+   - A map with :error, :message, and :diff or :new-source keys, and potentially :repaired"
   [ctx]
   (if (::form-pipeline/error ctx)
     {:error true
      :message (::form-pipeline/message ctx)}
-    (cond-> {:error false
-             :diff (::form-pipeline/diff ctx)
-             :type (::form-pipeline/type ctx)}
-      ;; Include repaired flag if present
-      (::form-pipeline/repaired ctx)
-      (assoc :repaired true))))
+    (let [dry_run (::dry-run ctx)]
+      (cond-> {:error false
+               :type (::form-pipeline/type ctx)}
+        ;; Include repaired flag if present
+        (::form-pipeline/repaired ctx)
+        (assoc :repaired true)
+
+        ;; Return new-source if dry-run is "new-source"
+        (= dry_run "new-source")
+        (assoc :new-source (::form-pipeline/output-source ctx))
+
+        ;; Otherwise return diff (default behavior and for "diff" dry-run)
+        (not= dry_run "new-source")
+        (assoc :diff (::form-pipeline/diff ctx))))))
 
 (comment
   ;; === Examples of using the file-edit pipeline directly ===

src/clojure_mcp/tools/file_edit/tool.clj

@@ -81,16 +81,16 @@ To make a file edit, provide the file_path, old_string (the text to replace), an
              :new_string new_string))))
 
 (defmethod tool-system/execute-tool :file-edit [{:keys [nrepl-client-atom] :as tool} inputs]
-  (let [{:keys [file_path old_string new_string]} inputs
-        result (pipeline/file-edit-pipeline file_path old_string new_string tool)]
+  (let [{:keys [file_path old_string new_string dry_run]} inputs
+        result (pipeline/file-edit-pipeline file_path old_string new_string dry_run tool)]
     (pipeline/format-result result)))
 
-(defmethod tool-system/format-results :file-edit [_ {:keys [error message diff type repaired]}]
+(defmethod tool-system/format-results :file-edit [_ {:keys [error message diff new-source type repaired]}]
   (if error
     {:error true
      :result [message]}
     (cond-> {:error false
-             :result [diff]
+             :result [(or new-source diff)]
              :type type}
       ;; Include repaired flag if present
       repaired (assoc :repaired true))))

src/clojure_mcp/tools/form_edit/combined_edit_tool.clj

@@ -126,8 +126,7 @@ Note: For `defmethod` forms, be sure to include the dispatch value (`area :recta
 ;; Validate inputs implementation
 (defmethod tool-system/validate-inputs :clojure-edit-form [{:keys [nrepl-client-atom]} inputs]
   (let [file-path (validate-file-path inputs nrepl-client-atom)
-        ;; Accept form_identifier but map it to form_name internally for compatibility
-        {:keys [form_identifier form_type operation content]} inputs
+        {:keys [form_identifier form_type operation content dry_run]} inputs
         form_name form_identifier]
     (when-not form_identifier
       (throw (ex-info "Missing required parameter: form_identifier"
@@ -145,30 +144,30 @@ Note: For `defmethod` forms, be sure to include the dispatch value (`area :recta
     (when-not content
       (throw (ex-info "Missing required parameter: content"
                       {:inputs inputs})))
-    ;; Return validated inputs with form_name for backward compatibility
     {:file_path file-path
      :form_name form_name
      :form_type form_type
      :operation operation
-     :content content}))
+     :content content
+     :dry_run dry_run}))
 
 ;; Execute tool implementation
 (defmethod tool-system/execute-tool :clojure-edit-form [{:keys [nrepl-client-atom] :as tool} inputs]
-  (let [{:keys [file_path form_name form_type operation content]} inputs
+  (let [{:keys [file_path form_name form_type operation content dry_run]} inputs
         edit-type (case operation
                     "replace" :replace
                     "insert_before" :before
                     "insert_after" :after)
-        result (pipeline/edit-form-pipeline file_path form_name form_type content edit-type tool)
+        result (pipeline/edit-form-pipeline file_path form_name form_type content edit-type dry_run tool)
         formatted-result (pipeline/format-result result)]
     formatted-result))
 
 ;; Format results implementation
-(defmethod tool-system/format-results :clojure-edit-form [_ {:keys [error message diff]}]
+(defmethod tool-system/format-results :clojure-edit-form [_ {:keys [error message diff new-source]}]
   (if error
     {:result [message]
      :error true}
-    {:result [diff]
+    {:result [(or new-source diff)]
      :error false}))
 
 ;; Tool registration function

src/clojure_mcp/tools/form_edit/pipeline.clj

@@ -43,14 +43,15 @@
 
 (s/def ::nrepl-client-atom (s/nilable #(instance? clojure.lang.Atom %)))
 
-;; Context map that flows through the pipeline
+(s/def ::dry-run (s/nilable #{"diff" "new-source"}))
+
 (s/def ::context
   (s/keys :req [::file-path]
           :opt [::source ::old-content ::new-source-code ::top-level-def-name
                 ::top-level-def-type ::edit-type ::error ::message
                 ::zloc ::offsets ::lint-result ::docstring
                 ::comment-substring ::new-content ::expand-symbols
-                ::diff ::type ::output-source ::nrepl-client-atom]))
+                ::diff ::type ::output-source ::nrepl-client-atom ::dry-run]))
 
 ;; Pipeline helper functions
 
@@ -536,16 +537,27 @@
    - ctx: The final context map from the pipeline
 
    Returns:
-   - A map with :error, :message, and possibly :offsets and :result keys"
+   - A map with :error, :message, and possibly :diff or :new-source, and :offsets keys"
   [ctx]
   (if (::error ctx)
     {:error true
      :message (::message ctx)}
-    (let [result-map {:error false}]
+    (let [dry_run (::dry-run ctx)
+          result-map {:error false}]
       (cond-> result-map
         (::offsets ctx) (assoc :offsets (::offsets ctx))
-        (::output-source ctx) (assoc :result [(::output-source ctx)])
-        (::diff ctx) (assoc :diff (::diff ctx))))))
+
+        ;; Return new-source if dry-run is "new-source"
+        (= dry_run "new-source")
+        (assoc :new-source (::output-source ctx))
+
+        ;; Otherwise return diff (default behavior and for "diff" dry-run)
+        (and (::diff ctx) (not= dry_run "new-source"))
+        (assoc :diff (::diff ctx))
+
+        ;; Legacy: include :result if output-source exists
+        (and (::output-source ctx) (not dry_run))
+        (assoc :result [(::output-source ctx)])))))
 
 ;; Pipeline function definitions
 
@@ -558,16 +570,17 @@
    - form-type: Type of form (e.g., 'defn', 'defmethod')
    - content-str: New content to insert
    - edit-type: Type of edit (:replace, :before, :after)
-   - nrepl-client-atom: Atom containing the nREPL client (optional)
-   - config: Optional tool configuration map
+   - dry-run: Optional string, either \"diff\" or \"new-source\" to skip actual file write
+   - config: Optional tool configuration map with :nrepl-client-atom
 
    Returns a context map with the result of the operation"
-  [file-path form-name form-type content-str edit-type {:keys [nrepl-client-atom] :as config}]
+  [file-path form-name form-type content-str edit-type dry_run {:keys [nrepl-client-atom] :as config}]
   (let [ctx {::file-path file-path
              ::top-level-def-name form-name
              ::top-level-def-type form-type
              ::new-source-code content-str
              ::edit-type edit-type
+             ::dry-run dry_run
              ::nrepl-client-atom nrepl-client-atom
              ::config config}]
     (thread-ctx
@@ -587,9 +600,13 @@
      format-source
      determine-file-type
      generate-diff
-     save-file
-     update-file-timestamp
-     highlight-form)))
+     (fn [ctx]
+       (if (::dry-run ctx)
+         ctx
+         (-> ctx
+             save-file
+             update-file-timestamp
+             highlight-form))))))
 
 (defn docstring-edit-pipeline
   "Pipeline for editing a docstring in a file.
@@ -769,17 +786,19 @@
    - operation: The operation to perform (:replace, :insert-before, :insert-after)
    - replace-all: Whether to apply the operation to all occurrences
    - whitespace-sensitive: Whether to match forms exactly as written
+   - dry_run: Optional string, either \"diff\" or \"new-source\" to skip actual file write
    - config: Optional tool configuration map with nrepl-client-atom
 
    Returns:
    - A context map with the result of the operation"
-  [file-path match-form new-form operation replace-all whitespace-sensitive {:keys [nrepl-client-atom] :as config}]
+  [file-path match-form new-form operation replace-all whitespace-sensitive dry_run {:keys [nrepl-client-atom] :as config}]
   (let [ctx {::file-path file-path
              ::match-form match-form
              ::new-form new-form
              ::operation operation
              ::replace-all replace-all
              ::whitespace-sensitive whitespace-sensitive
+             ::dry-run dry_run
              ::nrepl-client-atom nrepl-client-atom
              ::config config}]
     (thread-ctx
@@ -797,9 +816,13 @@
      format-source
      determine-file-type
      generate-diff
-     save-file
-     update-file-timestamp
-     highlight-form)))
+     (fn [ctx]
+       (if (::dry-run ctx)
+         ctx
+         (-> ctx
+             save-file
+             update-file-timestamp
+             highlight-form))))))
 
 (comment
   ;; Example usage of the pipelines

src/clojure_mcp/tools/form_edit/tool.clj

@@ -164,7 +164,7 @@ Note: For `defmethod` forms, be sure to include the dispatch value (`area :recta
 
 (defmethod tool-system/execute-tool :clojure-edit-replace-form [{:keys [nrepl-client-atom] :as tool} inputs]
   (let [{:keys [file_path form_name form_type content]} inputs
-        result (pipeline/edit-form-pipeline file_path form_name form_type content :replace tool)
+        result (pipeline/edit-form-pipeline file_path form_name form_type content :replace nil tool)
         formatted-result (pipeline/format-result result)]
     formatted-result))
 
@@ -256,7 +256,7 @@ Note: For `defmethod` forms, be sure to include the dispatch value (`area :recta
 
 (defmethod tool-system/execute-tool :clojure-edit-insert-before-form [{:keys [nrepl-client-atom] :as tool} inputs]
   (let [{:keys [file_path form_name form_type content]} inputs
-        result (pipeline/edit-form-pipeline file_path form_name form_type content :before tool)
+        result (pipeline/edit-form-pipeline file_path form_name form_type content :before nil tool)
         formatted-result (pipeline/format-result result)]
     formatted-result))
 
@@ -348,7 +348,7 @@ Note: For `defmethod` forms, be sure to include the dispatch value (`area :recta
 
 (defmethod tool-system/execute-tool :clojure-edit-insert-after-form [{:keys [nrepl-client-atom] :as tool} inputs]
   (let [{:keys [file_path form_name form_type content]} inputs
-        result (pipeline/edit-form-pipeline file_path form_name form_type content :after tool)
+        result (pipeline/edit-form-pipeline file_path form_name form_type content :after nil tool)
         formatted-result (pipeline/format-result result)]
     formatted-result))
 
@@ -545,7 +545,7 @@ For reliable results, use a unique substring that appears in only one comment bl
 (defmethod tool-system/validate-inputs :clojure-update-sexp
   [{:keys [nrepl-client-atom multi-op]} inputs]
   (let [file-path (validate-file-path inputs nrepl-client-atom)
-        {:keys [match_form new_form operation replace_all whitespace_sensitive]} inputs]
+        {:keys [match_form new_form operation replace_all whitespace_sensitive dry_run]} inputs]
     (when-not match_form
       (throw (ex-info "Missing required parameter: match_form"
                       {:inputs inputs})))
@@ -567,16 +567,9 @@ For reliable results, use a unique substring that appears in only one comment bl
       (throw (ex-info "Bad parameter: match-form can not be a blank string."
                       {:inputs inputs})))
 
-    ;; TODO we can get more sophisticated here...  we are handling
-    ;; code repairs deeper inside the actually tools evaluation and
-    ;; this prevents it.  Also I think we can actually do comment
-    ;; replacement now but we might need special handling for that.
-
-    ;; Special handling for empty string
     (when-not (str/blank? match_form)
       (try
         (let [parsed (p/parse-string-all match_form)]
-            ;; Check if there's at least one non-whitespace, non-comment node
           (when (zero? (count (n/child-sexprs parsed)))
             (throw (ex-info "match_form must contain at least one S-expression (not just comments or whitespace)"
                             {:inputs inputs}))))
@@ -587,41 +580,39 @@ For reliable results, use a unique substring that appears in only one comment bl
                             {:inputs inputs}))))))
 
     (when-not (str/blank? new_form)
-      ;; Validate that new_form is valid Clojure code
       (try
         (p/parse-string-all new_form)
         (catch Exception e
           (throw (ex-info (str "Invalid Clojure code in new_form: " (.getMessage e))
                           {:inputs inputs})))))
-    ;; Return validated inputs
     {:file_path file-path
      :match_form match_form
      :new_form new_form
      :operation operation
      :replace_all (boolean (if (#{"insert_before" "insert_after"} operation)
                              false
                              (or replace_all false)))
-     :whitespace_sensitive (boolean (or whitespace_sensitive false))}))
+     :whitespace_sensitive (boolean (or whitespace_sensitive false))
+     :dry_run dry_run}))
 
 (defmethod tool-system/execute-tool :clojure-update-sexp [{:keys [multi-op nrepl-client-atom] :as tool} inputs]
-  (let [{:keys [file_path match_form new_form operation replace_all whitespace_sensitive]} inputs
-        ;; Convert operation string to keyword for the pipeline
+  (let [{:keys [file_path match_form new_form operation replace_all whitespace_sensitive dry_run]} inputs
         operation-kw (if-not multi-op
                        :replace
                        (condp = operation
                          "replace" :replace
                          "insert_before" :insert-before
                          "insert_after" :insert-after))
         result (pipeline/sexp-edit-pipeline
-                file_path match_form new_form operation-kw replace_all whitespace_sensitive tool)
+                file_path match_form new_form operation-kw replace_all whitespace_sensitive dry_run tool)
         formatted-result (pipeline/format-result result)]
     formatted-result))
 
-(defmethod tool-system/format-results :clojure-update-sexp [_ {:keys [error message diff]}]
+(defmethod tool-system/format-results :clojure-update-sexp [_ {:keys [error message diff new-source]}]
   (if error
     {:result [message]
      :error true}
-    {:result [diff]
+    {:result [(or new-source diff)]
      :error false}))
 
 ;; Function to register the tool

test/clojure_mcp/tools/form_edit/pipeline_test.clj

@@ -294,6 +294,7 @@
                            "defn"
                            "(defn example-fn [x y]\n  (* x y))"
                            :replace
+                           nil
                            *nrepl-client-atom*)
           result (sut/format-result pipeline-result)
           file-content (slurp file-path)]
@@ -316,6 +317,7 @@
                            "comment"
                            "(comment some test comment)"
                            :replace
+                           nil
                            *nrepl-client-atom*)]
       (is (true? (::sut/error pipeline-result)))
       (is (string? (::sut/message pipeline-result)))