fix: reject unsupported custom emoji reactions

CHANGELOG.md

@@ -21,6 +21,7 @@
 - fix: confirm standard tapback reaction selection in Messages automation (#53, thanks @PeterRosdahl)
 - fix: gate RPC watch reaction metadata on `include_reactions`, not `attachments` (#82)
 - fix: dedupe URL balloon preview duplicates in watch stream without cross-chat/schema regressions (#64, thanks @lesaai)
+- fix: reject unsupported custom emoji reaction sends instead of emitting a no-op AppleScript path (#55)
 - fix: normalize IMCore typing chat lookup across `iMessage`, `SMS`, and `any` prefixes (#51, #54, #56, #58)
 - docs: document macOS 26 advanced IMCore injection limits (#60)
 - fix: report macOS 26/Tahoe IMCore typing entitlement failures as advanced-feature setup errors (#60)

README.md

@@ -91,6 +91,10 @@ imsg launch
 imsg typing --to "+14155551212" --duration 5s
 ```
 
+`imsg react` sends only the standard tapbacks exposed reliably through
+Messages.app automation. Custom emoji tapbacks can be read from history/watch
+output, but are not sent by the CLI.
+
 ## Attachment notes
 `--attachments` prints per-attachment lines with name, MIME, missing flag, and resolved path (tilde expanded). By default only metadata is shown; files aren’t copied.
 

Sources/IMsgCore/Errors.swift

@@ -8,6 +8,7 @@ public enum IMsgError: LocalizedError, Sendable {
   case appleScriptFailure(String)
   case typingIndicatorFailed(String)
   case invalidReaction(String)
+  case unsupportedReaction(String)
   case chatNotFound(chatID: Int64)
 
   public var errorDescription: String? {
@@ -45,8 +46,9 @@ public enum IMsgError: LocalizedError, Sendable {
         Invalid reaction: \(value)
 
         Valid reactions: love, like, dislike, laugh, emphasis, question
-        Or use an emoji for custom reactions (e.g., 🎉)
         """
+    case .unsupportedReaction(let message):
+      return "Unsupported reaction: \(message)"
     case .chatNotFound(let chatID):
       return "Chat not found: \(chatID)"
     }

Sources/imsg/Commands/ReactCommand.swift

@@ -16,7 +16,9 @@ enum ReactCommand {
 
       Reaction types:
         love (❤️), like (👍), dislike (👎), laugh (😂), emphasis (‼️), question (❓)
-        Or any single emoji for custom reactions (iOS 17+ / macOS 14+)
+
+      Custom emoji tapbacks can be read from history/watch output, but cannot be
+      sent reliably through Messages.app AppleScript automation.
       """,
     signature: CommandSignatures.withRuntimeFlags(
       CommandSignature(
@@ -24,7 +26,7 @@ enum ReactCommand {
           .make(label: "chatID", names: [.long("chat-id")], help: "chat rowid to react in"),
           .make(
             label: "reaction", names: [.long("reaction"), .short("r")],
-            help: "reaction type: love, like, dislike, laugh, emphasis, question, or emoji"),
+            help: "reaction type: love, like, dislike, laugh, emphasis, question"),
         ],
         flags: []
       )
@@ -32,7 +34,6 @@ enum ReactCommand {
     usageExamples: [
       "imsg react --chat-id 1 --reaction like",
       "imsg react --chat-id 1 -r love",
-      "imsg react --chat-id 1 -r 🎉",
     ]
   ) { values, runtime in
     try await run(values: values, runtime: runtime)
@@ -58,6 +59,12 @@ enum ReactCommand {
     if case .custom(let emoji) = reactionType, !isSingleEmoji(emoji) {
       throw IMsgError.invalidReaction(reactionString)
     }
+    if case .custom(let emoji) = reactionType {
+      throw IMsgError.unsupportedReaction(
+        "custom emoji tapback '\(emoji)' cannot be sent by Messages.app "
+          + "AppleScript automation; use love, like, dislike, laugh, emphasis, or question."
+      )
+    }
 
     // Get chat info for the GUID
     let dbPath = values.option("db") ?? MessageStore.defaultPath
@@ -103,40 +110,11 @@ enum ReactCommand {
     case .laugh: keyNumber = 4
     case .emphasis: keyNumber = 5
     case .question: keyNumber = 6
-    case .custom:
-      let script = """
-        on run argv
-          set chatGUID to item 1 of argv
-          set chatLookup to item 2 of argv
-          set customEmoji to item 3 of argv
-
-          tell application "Messages"
-            activate
-            set targetChat to chat id chatGUID
-          end tell
-
-          delay 0.3
-
-          tell application "System Events"
-            tell process "Messages"
-              keystroke "f" using command down
-              delay 0.15
-              keystroke "a" using command down
-              keystroke chatLookup
-              delay 0.25
-              key code 36
-              delay 0.35
-              keystroke "t" using command down
-              delay 0.2
-              keystroke customEmoji
-              delay 0.1
-              key code 36
-            end tell
-          end tell
-        end run
-        """
-      try appleScriptRunner(script, [chatGUID, chatLookup, reactionType.emoji])
-      return
+    case .custom(let emoji):
+      throw IMsgError.unsupportedReaction(
+        "custom emoji tapback '\(emoji)' cannot be sent by Messages.app "
+          + "AppleScript automation; use love, like, dislike, laugh, emphasis, or question."
+      )
     }
 
     let script = """

Tests/imsgTests/ReactCommandTests.swift

@@ -60,7 +60,7 @@ func reactCommandBuildsParameterizedAppleScriptForStandardTapback() async throws
 }
 
 @Test
-func reactCommandBuildsParameterizedAppleScriptForCustomEmoji() async throws {
+func reactCommandRejectsCustomEmojiSend() async throws {
   let path = try CommandTestDatabase.makePath()
   let values = ParsedValues(
     positional: [],
@@ -68,21 +68,25 @@ func reactCommandBuildsParameterizedAppleScriptForCustomEmoji() async throws {
     flags: []
   )
   let runtime = RuntimeOptions(parsedValues: values)
-  var capturedScript = ""
-  var capturedArguments: [String] = []
-  _ = try await StdoutCapture.capture {
+  do {
     try await ReactCommand.run(
       values: values,
       runtime: runtime,
-      appleScriptRunner: { source, arguments in
-        capturedScript = source
-        capturedArguments = arguments
+      appleScriptRunner: { _, _ in
+        #expect(Bool(false))
       }
     )
+    #expect(Bool(false))
+  } catch let error as IMsgError {
+    switch error {
+    case .unsupportedReaction(let message):
+      #expect(message.contains("custom emoji tapback"))
+      #expect(message.contains("AppleScript automation"))
+      #expect(message.contains("love"))
+    default:
+      #expect(Bool(false))
+    }
+  } catch {
+    #expect(Bool(false))
   }
-  #expect(capturedArguments == ["iMessage;+;chat123", "Test Chat", "🎉"])
-  #expect(capturedScript.contains("on run argv"))
-  #expect(capturedScript.contains("keystroke customEmoji"))
-  #expect(capturedScript.contains("key code 36"))
-  #expect(capturedScript.contains("chat123") == false)
 }