fix(ui): hide download action for local file attachments

Avoid showing a misleading download icon for file:// attachments in the message stream.

packages/ui/src/components/message-item.tsx

@@ -1,5 +1,5 @@
 import { For, Show, createSignal } from "solid-js"
-import { Copy, Split, Trash2, Undo } from "lucide-solid"
+import { Copy, ExternalLink, Split, Trash2, Undo } from "lucide-solid"
 import type { MessageInfo, ClientPart } from "../types/message"
 import { partHasRenderableText } from "../types/message"
 import type { MessageRecord } from "../stores/message-v2/types"
@@ -8,6 +8,7 @@ import { copyToClipboard } from "../lib/clipboard"
 import { useI18n } from "../lib/i18n"
 import { showAlertDialog } from "../stores/alerts"
 import { deleteMessagePart } from "../stores/session-actions"
+import { isTauriHost } from "../lib/runtime-env"
 
 interface MessageItemProps {
   record: MessageRecord
@@ -45,6 +46,15 @@ export default function MessageItem(props: MessageItemProps) {
 
   const messageParts = () => props.parts
 
+  // User messages can temporarily include synthetic helper parts (e.g. tool traces / file reads).
+  // We only want to display the primary prompt text for the user message; other synthetic text
+  // parts should be hidden.
+  const primaryUserTextPartId = () => {
+    if (!isUser()) return null
+    const firstText = messageParts().find((part) => part?.type === "text") as { id?: string } | undefined
+    return typeof firstText?.id === "string" ? firstText.id : null
+  }
+
   const fileAttachments = () =>
     messageParts().filter((part): part is FilePart => part?.type === "file" && typeof (part as FilePart).url === "string")
 
@@ -96,7 +106,8 @@ export default function MessageItem(props: MessageItemProps) {
     }
 
     if (url.startsWith("file://")) {
-      window.open(url, "_blank", "noopener")
+      // Local filesystem URLs are not reliably downloadable from the message stream.
+      // We hide the download action for these chips.
       return
     }
 
@@ -372,6 +383,7 @@ export default function MessageItem(props: MessageItemProps) {
               messageType={props.record.role}
               instanceId={props.instanceId}
               sessionId={props.sessionId}
+              primaryUserTextPartId={primaryUserTextPartId()}
               onRendered={props.onContentRendered}
             />
           )}
@@ -398,17 +410,20 @@ export default function MessageItem(props: MessageItemProps) {
                       <img src={attachment.url} alt={name} class="h-5 w-5 rounded object-cover" />
                     </Show>
                     <span class="truncate max-w-[180px]">{name}</span>
-                    <button
-                      type="button"
-                      onClick={() => void handleAttachmentDownload(attachment)}
-                      class="attachment-download"
-                      aria-label={t("messageItem.attachment.downloadAriaLabel", { name })}
-                    >
-                      <svg class="h-3 w-3" fill="none" viewBox="0 0 24 24" stroke="currentColor">
-                        <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 16v2a2 2 0 002 2h12a2 2 0 002-2v-2" />
-                        <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M8 12l4 4 4-4m-4-8v12" />
-                      </svg>
-                    </button>
+                    <Show when={!attachment.url?.startsWith("file://")}>
+                      <button
+                        type="button"
+                        onClick={() => void handleAttachmentDownload(attachment)}
+                        class="attachment-download"
+                        aria-label={t("messageItem.attachment.downloadAriaLabel", { name })}
+                        title={t("messageItem.attachment.downloadAriaLabel", { name })}
+                      >
+                        <svg class="h-3 w-3" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+                          <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 16v2a2 2 0 002 2h12a2 2 0 002-2v-2" />
+                          <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M8 12l4 4 4-4m-4-8v12" />
+                        </svg>
+                      </button>
+                    </Show>
 
                     <button
                       type="button"

packages/ui/src/components/message-part.tsx

@@ -13,9 +13,12 @@ interface MessagePartProps {
   messageType?: "user" | "assistant"
   instanceId: string
   sessionId: string
+  // For user messages, keep the primary prompt text visible even when synthetic (optimistic).
+  // Other synthetic text parts (tool traces, read outputs, etc.) should be hidden.
+  primaryUserTextPartId?: string | null
   onRendered?: () => void
  }
-  export default function MessagePart(props: MessagePartProps) {
+   export default function MessagePart(props: MessagePartProps) {
 
   const { isDark } = useTheme()
   const { preferences } = useConfig()
@@ -28,8 +31,19 @@ interface MessagePartProps {
   const shouldHideTextPart = () => {
     const part = props.part
     if (!part || part.type !== "text") return false
-    // Keep optimistic user prompts visible; hide synthetic assistant text.
-    return Boolean((part as any).synthetic) && props.messageType !== "user"
+
+    const isSynthetic = Boolean((part as any).synthetic)
+    if (!isSynthetic) return false
+
+    // Keep optimistic user prompts visible; hide other synthetic user helper parts.
+    if (props.messageType === "user") {
+      const primaryId = props.primaryUserTextPartId
+      if (!primaryId) return false
+      return part.id !== primaryId
+    }
+
+    // Hide synthetic assistant text.
+    return true
   }
 
 

packages/ui/src/components/prompt-input/usePromptKeyDown.ts

@@ -183,9 +183,25 @@ export function usePromptKeyDown(options: UsePromptKeyDownOptions) {
 
         if (isDeletingFromEnd || isDeletingFromStart || isSelected) {
           const currentAttachments = options.getAttachments()
-          const attachment = currentAttachments.find(
-            (a) => (a.source.type === "file" || a.source.type === "agent") && a.filename === name,
-          )
+          const attachment = currentAttachments.find((a) => {
+            if (a.source.type === "agent") {
+              return a.filename === name
+            }
+            if (a.source.type === "file") {
+              // Match either by filename (basename) or by path (for full paths like @docs/file.txt)
+              return (
+                a.filename === name ||
+                a.source.path === name ||
+                a.source.path.endsWith("/" + name) ||
+                a.source.path === name.replace(/\/$/, "")
+              )
+            }
+            if (a.source.type === "text") {
+              // For text attachments (path-only mentions), match by value
+              return a.source.value === name || a.source.value.endsWith("/" + name)
+            }
+            return false
+          })
 
           if (attachment) {
             e.preventDefault()
@@ -205,6 +221,14 @@ export function usePromptKeyDown(options: UsePromptKeyDownOptions) {
               textarea.setSelectionRange(mentionStart, mentionStart)
             }, 0)
 
+            // Check if there are any @ remaining in the text - if not, close the picker
+            if (!newText.includes("@") && options.isPickerOpen()) {
+              options.closePicker()
+              // Clear ignoredAtPositions since we deleted the entire @mention
+              // This ensures typing @ again will open the picker
+              options.setIgnoredAtPositions(new Set())
+            }
+
             return
           }
         }

packages/ui/src/components/prompt-input/usePromptPicker.ts

@@ -2,8 +2,9 @@ import { createSignal, type Accessor, type Setter } from "solid-js"
 import type { Command as SDKCommand } from "@opencode-ai/sdk/v2"
 import type { Agent } from "../../types/session"
 import { createAgentAttachment, createFileAttachment } from "../../types/attachment"
-import { addAttachment, getAttachments } from "../../stores/attachments"
+import { addAttachment, getAttachments, removeAttachment } from "../../stores/attachments"
 import type { PickerMode } from "./types"
+import type { PickerSelectAction } from "../unified-picker"
 
 type PickerItem =
   | { type: "agent"; agent: Agent }
@@ -37,7 +38,7 @@ type PromptPickerController = {
   setIgnoredAtPositions: Setter<Set<number>>
 
   handleInput: (e: Event) => void
-  handlePickerSelect: (item: PickerItem) => void
+  handlePickerSelect: (item: PickerItem, action: PickerSelectAction) => void
   handlePickerClose: () => void
 }
 
@@ -103,10 +104,11 @@ export function usePromptPicker(options: PromptPickerOptions): PromptPickerContr
     setAtPosition(null)
   }
 
-  function handlePickerSelect(item: PickerItem) {
+  function handlePickerSelect(item: PickerItem, action: PickerSelectAction) {
     const textarea = options.getTextarea()
 
     if (item.type === "command") {
+      // For commands, Tab/Enter/Shift+Enter/click all mean "select".
       const name = item.command.name
       const currentPrompt = options.prompt()
 
@@ -128,6 +130,7 @@ export function usePromptPicker(options: PromptPickerOptions): PromptPickerContr
         }
       }, 0)
     } else if (item.type === "agent") {
+      // For agents, Tab/Enter/Shift+Enter/click all mean "select".
       const agentName = item.agent.name
       const existingAttachments = getAttachments(options.instanceId(), options.sessionId())
       const alreadyAttached = existingAttachments.some(
@@ -163,76 +166,144 @@ export function usePromptPicker(options: PromptPickerOptions): PromptPickerContr
       const relativePath = item.file.relativePath ?? displayPath
       const isFolder = item.file.isDirectory ?? displayPath.endsWith("/")
 
-      if (isFolder) {
-        const currentPrompt = options.prompt()
-        const pos = atPosition()
-        const cursorPos = textarea?.selectionStart || 0
-        const folderMention =
-          relativePath === "." || relativePath === ""
-            ? "/"
-            : relativePath.replace(/\/+$/, "") + "/"
-
-        if (pos !== null) {
-          const before = currentPrompt.substring(0, pos + 1)
-          const after = currentPrompt.substring(cursorPos)
-          const newPrompt = before + folderMention + after
-          options.setPrompt(newPrompt)
-          setSearchQuery(folderMention)
-
-          setTimeout(() => {
-            const nextTextarea = options.getTextarea()
-            if (nextTextarea) {
-              const newCursorPos = pos + 1 + folderMention.length
-              nextTextarea.setSelectionRange(newCursorPos, newCursorPos)
-            }
-          }, 0)
-        }
-
-        return
-      }
-
-      const normalizedPath = relativePath.replace(/\/+$/, "") || relativePath
-      const pathSegments = normalizedPath.split("/")
-      const filename = (() => {
-        const candidate = pathSegments[pathSegments.length - 1] || normalizedPath
-        return candidate === "." ? "/" : candidate
-      })()
-
-      const existingAttachments = getAttachments(options.instanceId(), options.sessionId())
-      const alreadyAttached = existingAttachments.some(
-        (att) => att.source.type === "file" && att.source.path === normalizedPath,
-      )
-
-      if (!alreadyAttached) {
-        const attachment = createFileAttachment(
-          normalizedPath,
-          filename,
-          "text/plain",
-          undefined,
-          options.instanceFolder(),
-        )
-        addAttachment(options.instanceId(), options.sessionId(), attachment)
-      }
-
-      const currentPrompt = options.prompt()
       const pos = atPosition()
       const cursorPos = textarea?.selectionStart || 0
 
-      if (pos !== null) {
+      const replaceMentionToken = (mentionText: string, opts?: { trailingSpace?: boolean }) => {
+        if (pos === null) return
+        const currentPrompt = options.prompt()
         const before = currentPrompt.substring(0, pos)
         const after = currentPrompt.substring(cursorPos)
-        const attachmentText = `@${normalizedPath}`
-        const newPrompt = before + attachmentText + " " + after
-        options.setPrompt(newPrompt)
+        const suffix = opts?.trailingSpace ? " " : ""
+        const nextPrompt = before + mentionText + suffix + after
+        options.setPrompt(nextPrompt)
 
         setTimeout(() => {
           const nextTextarea = options.getTextarea()
-          if (nextTextarea) {
-            const newCursorPos = pos + attachmentText.length + 1
-            nextTextarea.setSelectionRange(newCursorPos, newCursorPos)
-          }
+          if (!nextTextarea) return
+          const nextCursorPos = pos + mentionText.length + suffix.length
+          nextTextarea.setSelectionRange(nextCursorPos, nextCursorPos)
         }, 0)
       }
+
+      const replaceMentionQueryAfterAt = (value: string) => {
+        // Replaces only the query after '@' (keeps the '@' itself). Used for directory navigation.
+        if (pos === null) return
+        const currentPrompt = options.prompt()
+        const before = currentPrompt.substring(0, pos + 1)
+        const after = currentPrompt.substring(cursorPos)
+        const nextPrompt = before + value + after
+        options.setPrompt(nextPrompt)
+
+        setTimeout(() => {
+          const nextTextarea = options.getTextarea()
+          if (!nextTextarea) return
+          const nextCursorPos = pos + 1 + value.length
+          nextTextarea.setSelectionRange(nextCursorPos, nextCursorPos)
+        }, 0)
+      }
+
+      const folderMention =
+        relativePath === "." || relativePath === ""
+          ? "/"
+          : relativePath.replace(/\/+$/, "") + "/"
+
+      const normalizedFolderPath = (() => {
+        const trimmed = relativePath.replace(/\/+$/, "")
+        return trimmed.length > 0 ? trimmed : "."
+      })()
+
+      if (isFolder) {
+        if (action === "tab") {
+          // TAB on directory: autocomplete directory name and show its contents.
+          replaceMentionQueryAfterAt(folderMention)
+          setSearchQuery(folderMention)
+          return
+        }
+
+        const mentionText = `@${folderMention}`
+
+        if (action === "shiftEnter") {
+          // SHIFT+ENTER on directory: keep @path in prompt (BACKSPACE works), remove @ when sending
+          replaceMentionToken(mentionText, { trailingSpace: true })
+        } else {
+          // ENTER/click on directory: attach as a file part pointing at a file:// directory URL.
+          const dirLabel =
+            normalizedFolderPath === "." ? "/" : normalizedFolderPath.split("/").pop() || normalizedFolderPath
+          const dirFilename = dirLabel.endsWith("/") ? dirLabel : `${dirLabel}/`
+
+          const existingAttachments = getAttachments(options.instanceId(), options.sessionId())
+          const alreadyAttached = existingAttachments.some(
+            (att) => att.source.type === "file" && att.source.path === normalizedFolderPath && att.source.mime === "inode/directory",
+          )
+
+          if (!alreadyAttached) {
+            // Remove any parent/child directory attachments that overlap with this one
+            // (e.g., if "docs/" is attached and user selects "docs/screenshots/", replace parent with child)
+            for (const att of existingAttachments) {
+              if (
+                att.source.type === "file" &&
+                att.source.mime === "inode/directory" &&
+                (normalizedFolderPath.startsWith(att.source.path + "/") || // new is child of existing
+                  att.source.path.startsWith(normalizedFolderPath + "/")) // new is parent of existing
+              ) {
+                // Remove the overlapping directory attachment
+                removeAttachment(options.instanceId(), options.sessionId(), att.id)
+              }
+            }
+
+            const attachment = createFileAttachment(
+              normalizedFolderPath,
+              dirFilename,
+              "inode/directory",
+              undefined,
+              options.instanceFolder(),
+            )
+            addAttachment(options.instanceId(), options.sessionId(), attachment)
+          }
+
+          replaceMentionToken(mentionText, { trailingSpace: true })
+        }
+      } else {
+        const normalizedPath = relativePath.replace(/\/+$/, "") || relativePath
+
+        if (action === "tab") {
+          // TAB on file: autocomplete the file path but do not attach.
+          replaceMentionToken(`@${normalizedPath}`)
+          setSearchQuery(normalizedPath)
+          return
+        }
+
+        if (action === "shiftEnter") {
+          // SHIFT+ENTER on file: keep @path in prompt (BACKSPACE works), remove @ when sending
+          replaceMentionToken(`@${normalizedPath}`, { trailingSpace: true })
+        } else {
+          // ENTER/click on file: attach file (existing behavior).
+          const pathSegments = normalizedPath.split("/")
+          const filename = (() => {
+            const candidate = pathSegments[pathSegments.length - 1] || normalizedPath
+            return candidate === "." ? "/" : candidate
+          })()
+
+          const existingAttachments = getAttachments(options.instanceId(), options.sessionId())
+          const alreadyAttached = existingAttachments.some(
+            (att) => att.source.type === "file" && att.source.path === normalizedPath,
+          )
+
+          if (!alreadyAttached) {
+            const attachment = createFileAttachment(
+              normalizedPath,
+              filename,
+              "text/plain",
+              undefined,
+              options.instanceFolder(),
+            )
+            addAttachment(options.instanceId(), options.sessionId(), attachment)
+          }
+
+          replaceMentionToken(`@${normalizedPath}`, { trailingSpace: true })
+        }
+      }
     }
 
     setShowPicker(false)
@@ -245,6 +316,25 @@ export function usePromptPicker(options: PromptPickerOptions): PromptPickerContr
     const pos = atPosition()
     if (pickerMode() === "mention" && pos !== null) {
       setIgnoredAtPositions((prev) => new Set(prev).add(pos))
+
+      // Remove the partial @mention text from the textarea when ESC is pressed
+      const textarea = options.getTextarea()
+      if (textarea) {
+        const currentPrompt = options.prompt()
+        const cursorPos = textarea.selectionStart
+        // Remove text from @ position to cursor position
+        const before = currentPrompt.substring(0, pos)
+        const after = currentPrompt.substring(cursorPos)
+        options.setPrompt(before + after)
+
+        // Restore cursor position to where @ was
+        setTimeout(() => {
+          const nextTextarea = options.getTextarea()
+          if (nextTextarea) {
+            nextTextarea.setSelectionRange(pos, pos)
+          }
+        }, 0)
+      }
     }
     setShowPicker(false)
     setAtPosition(null)

packages/ui/src/components/unified-picker.tsx

@@ -74,10 +74,12 @@ type PickerItem =
   | { type: "file"; file: FileItem }
   | { type: "command"; command: SDKCommand }
 
+export type PickerSelectAction = "click" | "tab" | "enter" | "shiftEnter"
+
 interface UnifiedPickerProps {
   open: boolean
   mode?: "mention" | "command"
-  onSelect: (item: PickerItem) => void
+  onSelect: (item: PickerItem, action: PickerSelectAction) => void
   onClose: () => void
   agents: Agent[]
   commands?: SDKCommand[]
@@ -266,6 +268,13 @@ const UnifiedPicker: Component<UnifiedPickerProps> = (props) => {
     const workspaceChanged = lastWorkspaceId !== props.workspaceId
     const queryChanged = lastQuery !== props.searchQuery
 
+    if (queryChanged) {
+      // Reset selectedIndex to 0 when query changes to avoid ghost state
+      // This ensures proper highlighting when navigating back to root or changing queries
+      setSelectedIndex(0)
+      resetScrollPosition()
+    }
+
     if (!isInitialized() || workspaceChanged || queryChanged) {
       setIsInitialized(true)
       lastWorkspaceId = props.workspaceId
@@ -356,7 +365,7 @@ const UnifiedPicker: Component<UnifiedPickerProps> = (props) => {
   }
 
   function handleSelect(item: PickerItem) {
-    props.onSelect(item)
+    props.onSelect(item, "click")
   }
 
   function handleKeyDown(e: KeyboardEvent) {
@@ -379,7 +388,8 @@ const UnifiedPicker: Component<UnifiedPickerProps> = (props) => {
       e.stopPropagation()
       const selected = items[selectedIndex()]
       if (selected) {
-        handleSelect(selected)
+        const action: PickerSelectAction = e.key === "Tab" ? "tab" : e.shiftKey ? "shiftEnter" : "enter"
+        props.onSelect(selected, action)
       }
     } else if (e.key === "Escape") {
       e.preventDefault()
@@ -443,7 +453,7 @@ const UnifiedPicker: Component<UnifiedPickerProps> = (props) => {
                   <div
                     class={`dropdown-item ${isSelected() ? "dropdown-item-highlight" : ""}`}
                     data-picker-selected={isSelected()}
-                    onClick={() => handleSelect({ type: "command", command })}
+                    onClick={() => props.onSelect({ type: "command", command }, "click")}
                   >
                     <div class="flex items-start gap-2">
                       <svg class="dropdown-icon-accent h-4 w-4 mt-0.5" fill="none" viewBox="0 0 24 24" stroke="currentColor">
@@ -479,7 +489,7 @@ const UnifiedPicker: Component<UnifiedPickerProps> = (props) => {
                       itemIndex === selectedIndex() ? "dropdown-item-highlight" : ""
                     }`}
                     data-picker-selected={itemIndex === selectedIndex()}
-                    onClick={() => handleSelect({ type: "agent", agent })}
+                    onClick={() => props.onSelect({ type: "agent", agent }, "click")}
                   >
                     <div class="flex items-start gap-2">
                       <svg
@@ -535,7 +545,7 @@ const UnifiedPicker: Component<UnifiedPickerProps> = (props) => {
                       itemIndex === selectedIndex() ? "dropdown-item-highlight" : ""
                     }`}
                     data-picker-selected={itemIndex === selectedIndex()}
-                    onClick={() => handleSelect({ type: "file", file })}
+                    onClick={() => props.onSelect({ type: "file", file }, "click")}
                   >
                     <div class="flex items-center gap-2 text-sm">
                       <Show

packages/ui/src/lib/prompt-placeholders.ts

@@ -1,12 +1,100 @@
-import type { Attachment } from "../types/attachment"
+import type { Attachment, FileSource } from "../types/attachment"
 
 export function resolvePastedPlaceholders(prompt: string, attachments: Attachment[] = []): string {
-  if (!prompt || !prompt.includes("[pasted #")) {
+  if (!prompt) {
     return prompt
   }
 
+  // First, strip `@` from path-like mentions that do NOT have a backing file attachment.
+  // This is intended for SHIFT+ENTER selection where we keep `@path` in the textarea for
+  // easy deletion, but send `path` to the API.
+  //
+  // IMPORTANT: avoid rewriting plain `@mentions` or email addresses.
+  const fileAttachmentPaths = new Set(
+    attachments
+      .filter((a): a is Attachment & { source: FileSource } => a.source.type === "file")
+      .map((a) => a.source.path),
+  )
+
+  const isPathLike = (value: string) => {
+    if (!value) return false
+    if (value.includes("/") || value.includes("\\")) return true
+    if (value.startsWith("./") || value.startsWith("../")) return true
+    if (value.startsWith("~")) return true
+    if (value.endsWith("/")) return true
+
+    // Root-level files (no `/`) still commonly have an extension.
+    const ext = value.split(".").pop()?.toLowerCase()
+    if (!ext || ext === value.toLowerCase()) return false
+
+    // Keep this list intentionally small and code-focused to avoid matching domains like `example.com`.
+    const allowedExts = new Set([
+      "ts",
+      "tsx",
+      "js",
+      "jsx",
+      "mjs",
+      "cjs",
+      "json",
+      "md",
+      "txt",
+      "yml",
+      "yaml",
+      "toml",
+      "css",
+      "html",
+      "htm",
+      "svg",
+      "png",
+      "jpg",
+      "jpeg",
+      "gif",
+      "pdf",
+      "rs",
+      "go",
+      "py",
+      "java",
+      "kt",
+      "swift",
+      "sh",
+      "bash",
+      "zsh",
+      "sql",
+      "lock",
+    ])
+    return allowedExts.has(ext)
+  }
+
+  const stripTrailingPunctuation = (value: string) => {
+    const match = value.match(/^(.*?)([)\]}.,!?:;]+)?$/)
+    if (!match) return { core: value, trailing: "" }
+    return { core: match[1] ?? value, trailing: match[2] ?? "" }
+  }
+
+  let result = prompt.replace(/(^|[\s([{"'`])@([^\s@]+)/g, (full, prefix, rawToken) => {
+    const { core, trailing } = stripTrailingPunctuation(String(rawToken))
+    if (!core) return full
+
+    // If this path has a file attachment, keep the `@` (attachment is sent separately).
+    if (fileAttachmentPaths.has(core) || fileAttachmentPaths.has(core.replace(/\/$/, ""))) {
+      return `${prefix}@${core}${trailing}`
+    }
+
+    // Only strip for path-like tokens; leave plain `@mentions` intact.
+    if (!isPathLike(core)) {
+      return `${prefix}@${core}${trailing}`
+    }
+
+    return `${prefix}${core}${trailing}`
+  })
+
+  // Then, resolve [pasted #N] placeholders
+  if (!result.includes("[pasted #")) {
+    return result
+  }
+
   if (!attachments || attachments.length === 0) {
-    return prompt
+    return result
   }
 
   const lookup = new Map<string, string>()
@@ -26,10 +114,10 @@ export function resolvePastedPlaceholders(prompt: string, attachments: Attachmen
   }
 
   if (lookup.size === 0) {
-    return prompt
+    return result
   }
 
-  return prompt.replace(/\[pasted #(\d+)\]/g, (fullMatch) => {
+  return result.replace(/\[pasted #(\d+)\]/g, (fullMatch) => {
     const replacement = lookup.get(fullMatch)
     return typeof replacement === "string" ? replacement : fullMatch
   })