feat(file-editor): configurable font family, size, and line height

Packages/macOS/CmuxSettings/Sources/CmuxSettings/Keys/FileEditorCatalogSection.swift

@@ -7,6 +7,35 @@ import Foundation
 /// is distinct from the rendered markdown viewer, whose settings live in
 /// ``MarkdownCatalogSection``.
 public struct FileEditorCatalogSection: SettingCatalogSection {
+    /// Default font size, in points, for newly opened editors.
+    ///
+    /// The editor's zoom shortcuts still adjust an individual editor on top of
+    /// this default and Cmd-0 returns to it.
+    public let fontSize = DefaultsKey<Int>(
+        id: "fileEditor.fontSize",
+        defaultValue: 13,
+        userDefaultsKey: "fileEditor.fontSize"
+    )
+
+    /// Default font family for newly opened editors.
+    ///
+    /// An empty value keeps the established monospaced system font.
+    public let fontFamily = DefaultsKey<String>(
+        id: "fileEditor.fontFamily",
+        defaultValue: "",
+        userDefaultsKey: "fileEditor.fontFamily"
+    )
+
+    /// Paragraph line-height multiplier for the editor.
+    ///
+    /// `1.0` preserves the natural font leading; larger values add readable
+    /// space between lines.
+    public let lineHeight = DefaultsKey<Double>(
+        id: "fileEditor.lineHeight",
+        defaultValue: 1.0,
+        userDefaultsKey: "fileEditor.lineHeight"
+    )
+
     /// Inclusive tab-stop range accepted by the editor and JSON schema.
     ///
     /// Keep this as a package-level constant so AppKit, the settings UI, and
@@ -15,7 +44,6 @@ public struct FileEditorCatalogSection: SettingCatalogSection {
 
     /// Inclusive tab-stop range accepted by the editor and JSON schema.
     public var tabWidthRange: ClosedRange<Int> { Self.supportedTabWidthRange }
-
     /// Whether long lines soft-wrap at the editor's right edge.
     ///
     /// `false` (the default) preserves the established behavior: lines extend

Packages/macOS/CmuxSettingsUI/Sources/CmuxSettingsUI/Navigation/CuratedSettingEntry+Default.swift

@@ -47,6 +47,33 @@ extension Array where Element == CuratedSettingEntry {
             .init(section: .app, id: "preferred-editor", title: "Open Files With", synonyms: "app.preferredEditor editor open file code vscode visual studio zed sublime subl cursor"),
             .init(section: .app, id: "supported-file-previews", title: "Open Supported Files in cmux", synonyms: "app.openSupportedFilesInCmux cmd click file preview pdf image video audio quicklook quick look editor external"),
             .init(section: .app, id: "markdown-viewer", title: "Open Markdown in cmux Viewer", synonyms: "app.openMarkdownInCmuxViewer md markdown mdx viewer preview readme"),
+            .init(
+                section: .app,
+                id: "file-editor-font-size",
+                title: String(localized: "settings.app.fileEditorFontSize", defaultValue: "File Editor Font Size"),
+                synonyms: String(
+                    localized: "settings.search.alias.setting.app.file-editor-font-size",
+                    defaultValue: "fileEditor.fontSize file editor font size points zoom scale text bigger smaller larger default"
+                )
+            ),
+            .init(
+                section: .app,
+                id: "file-editor-font-family",
+                title: String(localized: "settings.app.fileEditorFontFamily", defaultValue: "File Editor Font"),
+                synonyms: String(
+                    localized: "settings.search.alias.setting.app.file-editor-font-family",
+                    defaultValue: "fileEditor.fontFamily file editor font family typeface system mono custom"
+                )
+            ),
+            .init(
+                section: .app,
+                id: "file-editor-line-height",
+                title: String(localized: "settings.app.fileEditorLineHeight", defaultValue: "File Editor Line Height"),
+                synonyms: String(
+                    localized: "settings.search.alias.setting.app.file-editor-line-height",
+                    defaultValue: "fileEditor.lineHeight file editor line height leading spacing paragraph line multiplier"
+                )
+            ),
             .init(section: .app, id: "file-editor-word-wrap", title: String(localized: "settings.app.fileEditorWordWrap", defaultValue: "File Editor Word Wrap"), synonyms: "fileEditor.wordWrap " + String(localized: "settings.search.fileEditor.wordWrap", defaultValue: "file editor word wrap soft wrap reflow lines text horizontal scroll preview")),
             .init(
                 section: .app,

Packages/macOS/CmuxSettingsUI/Sources/CmuxSettingsUI/Sections/AppSection.swift

@@ -8,7 +8,7 @@ import SwiftUI
 /// Keep Workspace Open When Closing Last Surface, Focus Pane on
 /// First Click, File Drops, Open Files With, Open Supported Files in
 /// cmux, Terminal Config link, Open Markdown in cmux Viewer,
-/// Markdown Viewer typography, iMessage Mode, Reorder on Notification, Dock Badge, Menu Bar
+/// Markdown Viewer typography, File Editor typography, iMessage Mode, Reorder on Notification, Dock Badge, Menu Bar
 /// Only, Show in Menu Bar, Unread Pane Ring, Pane Flash, Desktop
 /// Notifications, Notification Sound, Notification Command, Send
 /// anonymous telemetry, Warn Before Quit, Warn Before Closing Tab /
@@ -41,6 +41,11 @@ public struct AppSection: View {
     @State private var markdownMaxWidth: DefaultsValueModel<Int>
     @State private var canvasPaneGap: DefaultsValueModel<Int>
     @State private var canvasSnapping: DefaultsValueModel<Bool>
+    @State private var fileEditorFontSize: DefaultsValueModel<Int>
+    @State private var fileEditorFontFamily: DefaultsValueModel<String>
+    @State private var fileEditorFontFamilyDraft = ""
+    @State private var fileEditorFontFamilyDraftLoaded = false
+    @State private var fileEditorLineHeight: DefaultsValueModel<Double>
     @State private var fileEditorWordWrap: DefaultsValueModel<Bool>
     @State private var fileEditorSyntaxHighlighting: DefaultsValueModel<Bool>
     @State private var fileEditorLineNumbers: DefaultsValueModel<Bool>
@@ -103,6 +108,9 @@ public struct AppSection: View {
         _markdownMaxWidth = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.markdown.maxWidth))
         _canvasPaneGap = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.canvas.paneGap))
         _canvasSnapping = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.canvas.snappingEnabled))
+        _fileEditorFontSize = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.fileEditor.fontSize))
+        _fileEditorFontFamily = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.fileEditor.fontFamily))
+        _fileEditorLineHeight = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.fileEditor.lineHeight))
         _fileEditorWordWrap = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.fileEditor.wordWrap))
         _fileEditorSyntaxHighlighting = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.fileEditor.syntaxHighlighting))
         _fileEditorLineNumbers = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.fileEditor.lineNumbers))
@@ -155,15 +163,24 @@ public struct AppSection: View {
             mainCard
         }
         .task {
-            startSettingsObservation([language, appearance, appIcon, placement, inheritDir, minimalMode, keepWorkspaceOpen, firstClick, focusHistoryIncludesPanesAndTabs, fileDrop, preferredEditor, openSupported, openMarkdown, globalFontMagnification, markdownFontSize, markdownFontFamily, markdownMaxWidth, canvasPaneGap, canvasSnapping, fileEditorWordWrap, fileEditorSyntaxHighlighting, fileEditorLineNumbers, fileEditorIndentGuides, fileEditorCurrentLineHighlight, fileEditorTabWidth, iMessage, reorder, dockBadge, menuBarOnly, showInMenuBar, paneRing, paneFlash, desktopNotifications, agentPermissionPrompt, agentTurnComplete, agentIdleReminder, soundName, soundCommand, customSoundFile, soundOverrides, telemetry, confirmQuit, warnCloseTab, warnCloseX, hideCloseButton, renameSelects, paletteAllSurfaces])
+            startSettingsObservation([language, appearance, appIcon, placement, inheritDir, minimalMode, keepWorkspaceOpen, firstClick, focusHistoryIncludesPanesAndTabs, fileDrop, preferredEditor, openSupported, openMarkdown, globalFontMagnification, markdownFontSize, markdownFontFamily, markdownMaxWidth, canvasPaneGap, canvasSnapping, fileEditorFontSize, fileEditorFontFamily, fileEditorLineHeight, fileEditorWordWrap, fileEditorSyntaxHighlighting, fileEditorLineNumbers, fileEditorIndentGuides, fileEditorCurrentLineHighlight, fileEditorTabWidth, iMessage, reorder, dockBadge, menuBarOnly, showInMenuBar, paneRing, paneFlash, desktopNotifications, agentPermissionPrompt, agentTurnComplete, agentIdleReminder, soundName, soundCommand, customSoundFile, soundOverrides, telemetry, confirmQuit, warnCloseTab, warnCloseX, hideCloseButton, renameSelects, paletteAllSurfaces])
             if soundAgents.isEmpty {
                 soundAgents = await hostActions.notificationSoundAgentOptions()
             }
+            if !fileEditorFontFamilyDraftLoaded {
+                fileEditorFontFamilyDraft = fileEditorFontFamily.current
+                fileEditorFontFamilyDraftLoaded = true
+            }
             if languageAtAppear == nil { languageAtAppear = language.current }; if telemetryAtAppear == nil { telemetryAtAppear = telemetry.current }
         }
         .onChange(of: soundOverrides.current) { _, newValue in
             soundOverridesModel.accept(newValue)
         }
+        .onChange(of: fileEditorFontFamily.current) { _, newValue in
+            if fileEditorFontFamilyDraft != newValue {
+                fileEditorFontFamilyDraft = newValue
+            }
+        }
     }
 
     private var globalFontMagnificationSubtitle: String {
@@ -184,6 +201,12 @@ public struct AppSection: View {
         globalFontMagnification.set(clamped) { NotificationCenter.default.post(name: GlobalFontMagnification.didChangeNotification, object: nil) }
     }
 
+    /// Persists the loaded font-family draft when editing ends or submits.
+    private func commitFileEditorFontFamilyDraft() {
+        guard fileEditorFontFamilyDraftLoaded else { return }
+        fileEditorFontFamily.set(fileEditorFontFamilyDraft)
+    }
+
     @ViewBuilder
     private var mainCard: some View {
         SettingsCard {
@@ -521,6 +544,75 @@ public struct AppSection: View {
             }
             SettingsCardDivider()
 
+            // File Editor Font Size
+            SettingsCardRow(
+                configurationReview: .json("fileEditor.fontSize"),
+                String(localized: "settings.app.fileEditorFontSize", defaultValue: "File Editor Font Size"),
+                subtitle: String(localized: "settings.app.fileEditorFontSize.subtitle", defaultValue: "Default font size, in points, for newly opened plain-text editors. Cmd-+ / Cmd-- / Cmd-0 zoom the current editor."),
+                controlWidth: Self.columnWidth
+            ) {
+                Stepper(
+                    value: Binding(get: { fileEditorFontSize.current }, set: { fileEditorFontSize.set($0) }),
+                    in: 8...36
+                ) {
+                    Text(verbatim: "\(fileEditorFontSize.current)")
+                        .monospacedDigit()
+                        .frame(width: 28, alignment: .trailing)
+                }
+                .controlSize(.small)
+                .accessibilityIdentifier("SettingsFileEditorFontSizeStepper")
+                .accessibilityLabel(
+                    String(localized: "settings.app.fileEditorFontSize", defaultValue: "File Editor Font Size")
+                )
+            }
+            SettingsCardDivider()
+
+            // File Editor Font Family
+            SettingsCardRow(
+                configurationReview: .json("fileEditor.fontFamily"),
+                String(localized: "settings.app.fileEditorFontFamily", defaultValue: "File Editor Font"),
+                subtitle: String(localized: "settings.app.fileEditorFontFamily.subtitle", defaultValue: "Default font family for newly opened plain-text editors. Leave empty for the system monospaced font.")
+            ) {
+                TextField(
+                    String(localized: "settings.app.fileEditorFontFamily.placeholder", defaultValue: "System Mono"),
+                    text: $fileEditorFontFamilyDraft,
+                    onEditingChanged: { isEditing in
+                        if !isEditing {
+                            commitFileEditorFontFamilyDraft()
+                        }
+                    },
+                    onCommit: { commitFileEditorFontFamilyDraft() }
+                )
+                .textFieldStyle(.roundedBorder)
+                .frame(width: 200)
+                .accessibilityIdentifier("SettingsFileEditorFontFamilyTextField")
+                .onDisappear { commitFileEditorFontFamilyDraft() }
+            }
+            SettingsCardDivider()
+
+            // File Editor Line Height
+            SettingsCardRow(
+                configurationReview: .json("fileEditor.lineHeight"),
+                String(localized: "settings.app.fileEditorLineHeight", defaultValue: "File Editor Line Height"),
+                subtitle: String(localized: "settings.app.fileEditorLineHeight.subtitle", defaultValue: "Line-height multiplier for plain-text editors. 1.0 preserves the font's natural spacing.")
+            ) {
+                Stepper(
+                    value: Binding(get: { fileEditorLineHeight.current }, set: { fileEditorLineHeight.set($0) }),
+                    in: 0.5...3.0,
+                    step: 0.1
+                ) {
+                    Text(verbatim: String(format: "%.1f", fileEditorLineHeight.current))
+                        .monospacedDigit()
+                        .frame(width: 32, alignment: .trailing)
+                }
+                .controlSize(.small)
+                .accessibilityIdentifier("SettingsFileEditorLineHeightStepper")
+                .accessibilityLabel(
+                    String(localized: "settings.app.fileEditorLineHeight", defaultValue: "File Editor Line Height")
+                )
+            }
+            SettingsCardDivider()
+
             // File Editor Word Wrap
             SettingsCardRow(
                 configurationReview: .json("fileEditor.wordWrap"),

Packages/macOS/CmuxSettingsUI/Tests/CmuxSettingsUITests/SettingsRowAnchorResolutionTests.swift

@@ -84,6 +84,9 @@ struct SettingsRowAnchorResolutionTests {
         "canvas.snappingEnabled",
         "cloud.beta.machines.enabled",
         "customSidebars.renderer",
+        "fileEditor.fontFamily",
+        "fileEditor.fontSize",
+        "fileEditor.lineHeight",
         "fileEditor.currentLineHighlight",
         "fileEditor.indentGuides",
         "fileEditor.lineNumbers",