✨ feat: integrate forward incremental search

src/ecro/bindings.clj

@@ -13,6 +13,8 @@
     (-> (keymap/make-keymap)
         (keymap/define-key ["C-a"] :move-beginning-of-line)
         (keymap/define-key ["C-e"] :move-end-of-line)
+        (keymap/define-key ["C-r"] :isearch-backward)
+        (keymap/define-key ["C-s"] :isearch-forward)
         (keymap/define-key ["C-k"] :kill-line)
         (keymap/define-key ["C-z"] :undo)
         (keymap/define-key ["C-S-z"] :redo)

src/ecro/command.clj

@@ -8,6 +8,7 @@
     [ecro.mode :as mode]
     [ecro.notification :as notification]
     [ecro.scroll :as scroll]
+    [ecro.search :as search]
     [ecro.state :as state]
     [ecro.undo :as undo]))
 
@@ -57,6 +58,18 @@
              :minibuffer (ecro.minibuffer/prompt-for "Write file: " :write-file)
              :key-sequence [])
 
+      (= command :isearch-forward)
+      (assoc editor-state
+             :isearch (assoc (search/make-isearch :forward)
+                             :start-point (:point buf))
+             :key-sequence [])
+
+      (= command :isearch-backward)
+      (assoc editor-state
+             :isearch (assoc (search/make-isearch :backward)
+                             :start-point (:point buf))
+             :key-sequence [])
+
       (= command :list-buffers)
       (state/list-buffers editor-state)
 

src/ecro/key.clj

@@ -8,12 +8,19 @@
     [ecro.native :as native]
     [ecro.render :as render]
     [ecro.scroll :as scroll]
+    [ecro.search :as search]
     [ecro.skk.input :as skk-input]
     [ecro.skk.sources :as skk-sources]
     [ecro.skk.state :as skk-state]
     [ecro.state :as state]))
 
 
+(def control-modifier 1)
+
+
+(def alt-modifier 2)
+
+
 (def shift-modifier 4)
 
 
@@ -114,6 +121,75 @@
       :else state)))
 
 
+(defn- code-point-string
+  "Convert a valid Unicode code point to a string."
+  [key-code]
+  (when (Character/isValidCodePoint key-code)
+    (String. (Character/toChars key-code))))
+
+
+(defn- terminal-sentinel-key-code?
+  "Return true for non-character key codes reserved by the terminal adapter."
+  [key-code]
+  (or (<= 1001 key-code 1010)
+      (<= 2001 key-code 2255)))
+
+
+(defn- repeat-isearch
+  [editor-state direction]
+  (let [isearch (assoc (:isearch editor-state) :direction direction)
+        buf (search/isearch-repeat isearch
+                                   (:current-buffer editor-state)
+                                   direction)
+        isearch (assoc isearch :anchor-point (:point buf))]
+    (-> editor-state
+        (assoc :isearch isearch)
+        (state/assoc-current-buffer buf))))
+
+
+(defn- handle-isearch-key
+  "Handle a key event while incremental search is active."
+  [editor-state key-code modifiers]
+  (cond
+    (= key-code 13)
+    (dissoc editor-state :isearch)
+
+    (= key-code 27)
+    (let [buf (search/isearch-cancel (:isearch editor-state)
+                                     (:current-buffer editor-state))]
+      (-> editor-state
+          (dissoc :isearch)
+          (state/assoc-current-buffer buf)))
+
+    (= key-code 127)
+    (let [isearch (search/isearch-delete-char (:isearch editor-state))
+          buf (search/isearch-execute isearch (:current-buffer editor-state))]
+      (-> editor-state
+          (assoc :isearch isearch)
+          (state/assoc-current-buffer buf)))
+
+    (and (= key-code (int \s)) (= modifiers control-modifier))
+    (repeat-isearch editor-state :forward)
+
+    (and (= key-code (int \r)) (= modifiers control-modifier))
+    (repeat-isearch editor-state :backward)
+
+    (terminal-sentinel-key-code? key-code)
+    editor-state
+
+    (and (>= key-code 32)
+         (zero? (bit-and modifiers (bit-or control-modifier alt-modifier))))
+    (if-let [text (code-point-string key-code)]
+      (let [isearch (search/isearch-add-char (:isearch editor-state) text)
+            buf (search/isearch-execute isearch (:current-buffer editor-state))]
+        (-> editor-state
+            (assoc :isearch isearch)
+            (state/assoc-current-buffer buf)))
+      editor-state)
+
+    :else editor-state))
+
+
 (defn- skk-active?
   "Return true if SKK minor mode is active in the current buffer."
   [editor-state]
@@ -213,15 +289,17 @@
 (defn handle-key
   "Handle a key event and return updated state."
   [editor-state key-code modifiers]
-  (if (:minibuffer editor-state)
-    (handle-minibuffer-key editor-state key-code)
-    (let [key-str (key-name key-code modifiers)]
-      (if (and (skk-active? editor-state)
-               (not (seq (:key-sequence editor-state)))
-               (not (= "ESC" key-str)))
-        (or (skk-handle-key editor-state key-str key-code)
-            (handle-regular-key editor-state key-code modifiers))
-        (handle-regular-key editor-state key-code modifiers)))))
+  (if (:isearch editor-state)
+    (handle-isearch-key editor-state key-code modifiers)
+    (if (:minibuffer editor-state)
+      (handle-minibuffer-key editor-state key-code)
+      (let [key-str (key-name key-code modifiers)]
+        (if (and (skk-active? editor-state)
+                 (not (seq (:key-sequence editor-state)))
+                 (not (= "ESC" key-str)))
+          (or (skk-handle-key editor-state key-str key-code)
+              (handle-regular-key editor-state key-code modifiers))
+          (handle-regular-key editor-state key-code modifiers))))))
 
 
 (defn process-event

src/ecro/render.clj

@@ -55,8 +55,18 @@
 (defn status-line
   "Build the status line string from editor state."
   [state]
-  (if-let [mb (:minibuffer state)]
-    (str (:prompt mb) (:text (:buffer mb)))
+  (cond
+    (:isearch state)
+    (str (if (= :backward (get-in state [:isearch :direction]))
+           "I-search backward: "
+           "I-search: ")
+         (get-in state [:isearch :pattern]))
+
+    (:minibuffer state)
+    (let [mb (:minibuffer state)]
+      (str (:prompt mb) (:text (:buffer mb))))
+
+    :else
     (let [buf (:current-buffer state)
           name (or (:name buf) "*scratch*")
           modified (if (not= (:text buf) (:saved-text buf)) "*" "")

src/ecro/search.clj

@@ -35,17 +35,46 @@
   (update state :pattern str ch))
 
 
+(defn isearch-delete-char
+  "Remove the last character from the i-search pattern."
+  [state]
+  (update state :pattern
+          (fn [^String pattern]
+            (if (empty? pattern)
+              pattern
+              (subs pattern 0 (.offsetByCodePoints pattern (count pattern) -1))))))
+
+
 (defn isearch-execute
   "Execute i-search with current pattern. Returns updated buffer."
   [state buf]
   (let [pattern (:pattern state)
-        start-point (or (:start-point state) (:point buf))]
+        start-point (or (:start-point state) (:point buf))
+        anchor-point (:anchor-point state)
+        search-point (if (some? anchor-point)
+                       (if (= :backward (:direction state))
+                         (inc anchor-point)
+                         anchor-point)
+                       start-point)
+        fallback-point (or anchor-point start-point)]
     (if (seq pattern)
       (let [result (case (:direction state)
-                     :forward (search-forward (assoc buf :point start-point) pattern)
-                     :backward (search-backward (assoc buf :point start-point) pattern))]
-        (or result (assoc buf :point start-point)))
-      buf)))
+                     :forward (search-forward (assoc buf :point search-point) pattern)
+                     :backward (search-backward (assoc buf :point search-point) pattern))]
+        (or result (assoc buf :point fallback-point)))
+      (assoc buf :point fallback-point))))
+
+
+(defn isearch-repeat
+  "Repeat the current i-search from the current match in direction."
+  [state buf direction]
+  (let [pattern (:pattern state)
+        point (:point buf)
+        result (when (seq pattern)
+                 (case direction
+                   :forward (search-forward (assoc buf :point (inc point)) pattern)
+                   :backward (search-backward (assoc buf :point point) pattern)))]
+    (or result buf)))
 
 
 (defn isearch-cancel

test/ecro/key_test.clj

@@ -4,7 +4,8 @@
     [clojure.test :refer :all]
     [ecro.bindings :as bindings]
     [ecro.buffer :as b]
-    [ecro.key :as key]))
+    [ecro.key :as key]
+    [ecro.render :as render]))
 
 
 (deftest test-key-name-control-shift-and-control-slash
@@ -45,6 +46,131 @@
       (is (= "Find file: " (get-in new-state [:minibuffer :prompt]))))))
 
 
+(deftest test-forward-incremental-search-integration
+  (testing "C-s searches as characters are typed and RET accepts the match"
+    (let [state {:current-buffer (assoc (b/make-buffer "test")
+                                        :text "hello world")
+                 :keymap bindings/default-keymap
+                 :key-sequence []}
+          started (key/handle-key state (int \s) 1)
+          with-w (key/handle-key started (int \w) 0)
+          with-wo (key/handle-key with-w (int \o) 0)
+          accepted (key/handle-key with-wo 13 0)]
+      (is (= {:pattern "" :direction :forward :start-point 0}
+             (:isearch started)))
+      (is (= 6 (get-in with-w [:current-buffer :point])))
+      (is (= "wo" (get-in with-wo [:isearch :pattern])))
+      (is (= "I-search: wo" (render/status-line with-wo)))
+      (is (= 6 (get-in accepted [:current-buffer :point])))
+      (is (nil? (:isearch accepted))))))
+
+
+(deftest test-backward-incremental-search-integration
+  (testing "C-r searches backward as characters are typed"
+    (let [state {:current-buffer (assoc (b/make-buffer "test")
+                                        :text "foo bar foo"
+                                        :point 11)
+                 :keymap bindings/default-keymap
+                 :key-sequence []}
+          started (key/handle-key state (int \r) 1)
+          searched (key/handle-key started (int \b) 0)]
+      (is (= :backward (get-in started [:isearch :direction])))
+      (is (= "b" (get-in searched [:isearch :pattern])))
+      (is (= 4 (get-in searched [:current-buffer :point])))
+      (is (= "I-search backward: b" (render/status-line searched))))))
+
+
+(deftest test-incremental-search-backspace
+  (testing "BS removes the last query character and recomputes the match"
+    (let [state {:current-buffer (assoc (b/make-buffer "test")
+                                        :text "hello world")
+                 :keymap bindings/default-keymap
+                 :key-sequence []}
+          started (key/handle-key state (int \s) 1)
+          searched (key/handle-key started (int \w) 0)
+          cleared (key/handle-key searched 127 0)]
+      (is (= 6 (get-in searched [:current-buffer :point])))
+      (is (= "" (get-in cleared [:isearch :pattern])))
+      (is (= 0 (get-in cleared [:current-buffer :point]))))))
+
+
+(deftest test-incremental-search-cancel
+  (testing "ESC cancels search and restores the starting point"
+    (let [state {:current-buffer (assoc (b/make-buffer "test")
+                                        :text "hello world"
+                                        :point 2)
+                 :keymap bindings/default-keymap
+                 :key-sequence []}
+          started (key/handle-key state (int \s) 1)
+          searched (key/handle-key started (int \w) 0)
+          canceled (key/handle-key searched 27 0)]
+      (is (= 6 (get-in searched [:current-buffer :point])))
+      (is (= 2 (get-in canceled [:current-buffer :point])))
+      (is (nil? (:isearch canceled))))))
+
+
+(deftest test-incremental-search-non-bmp-character
+  (testing "a non-BMP code point can be added and removed as one character"
+    (let [state {:current-buffer (assoc (b/make-buffer "test")
+                                        :text "a😀b")
+                 :keymap bindings/default-keymap
+                 :key-sequence []}
+          started (key/handle-key state (int \s) 1)
+          searched (key/handle-key started 0x1F600 0)
+          cleared (key/handle-key searched 127 0)]
+      (is (= "😀" (get-in searched [:isearch :pattern])))
+      (is (= 1 (get-in searched [:current-buffer :point])))
+      (is (= "" (get-in cleared [:isearch :pattern])))
+      (is (= 0 (get-in cleared [:current-buffer :point]))))))
+
+
+(deftest test-incremental-search-ignores-terminal-sentinel-codes
+  (testing "navigation and function key sentinels do not enter the query"
+    (let [state {:current-buffer (assoc (b/make-buffer "test")
+                                        :text "hello world")
+                 :keymap bindings/default-keymap
+                 :key-sequence []}
+          started (key/handle-key state (int \s) 1)
+          searched (key/handle-key started (int \w) 0)
+          after-specials (reduce #(key/handle-key %1 %2 0)
+                                 searched
+                                 [1001 1004 1005 1010 2001])]
+      (is (= "w" (get-in after-specials [:isearch :pattern])))
+      (is (= 6 (get-in after-specials [:current-buffer :point]))))))
+
+
+(deftest test-incremental-search-classifies-modifiers
+  (testing "Shift text is accepted while unrelated Ctrl and Alt chords are ignored"
+    (let [state {:current-buffer (assoc (b/make-buffer "test") :text "W")
+                 :keymap bindings/default-keymap
+                 :key-sequence []}
+          started (key/handle-key state (int \s) 1)
+          shifted (key/handle-key started (int \W) key/shift-modifier)
+          after-chords (-> shifted
+                           (key/handle-key (int \g) 1)
+                           (key/handle-key (int \x) 2))]
+      (is (= "W" (get-in after-chords [:isearch :pattern])))
+      (is (= 0 (get-in after-chords [:current-buffer :point]))))))
+
+
+(deftest test-incremental-search-repeat-controls
+  (testing "C-s and C-r repeat the query without entering command characters"
+    (let [state {:current-buffer (assoc (b/make-buffer "test")
+                                        :text "foo foo foo")
+                 :keymap bindings/default-keymap
+                 :key-sequence []}
+          started (key/handle-key state (int \s) 1)
+          searched (key/handle-key started (int \f) 0)
+          next-match (key/handle-key searched (int \s) 1)
+          refined (key/handle-key next-match (int \o) 0)
+          previous-match (key/handle-key refined (int \r) 1)]
+      (is (= 4 (get-in next-match [:current-buffer :point])))
+      (is (= 4 (get-in refined [:current-buffer :point])))
+      (is (= 0 (get-in previous-match [:current-buffer :point])))
+      (is (= "fo" (get-in previous-match [:isearch :pattern])))
+      (is (= :backward (get-in previous-match [:isearch :direction]))))))
+
+
 (deftest test-minibuffer-switch-to-buffer
   (testing "minibuffer Enter switches to named buffer"
     (let [state {:minibuffer {:buffer {:text "other.clj"}