Keep hover and pointer overrides on desktop set_viewport

CHANGELOG.md

@@ -5,6 +5,8 @@
 ### Changed
 
 ### Fixed
+- `set_viewport` and `resize` turned touch emulation off on every desktop viewport, which reset hover and pointer and
+  undid `--blink-settings` overrides. `mobile:` defaults to `nil` and leaves touch as is, `false` turns it off [#664]
 
 ### Removed
 

docs/14-emulation.md

@@ -14,7 +14,8 @@ Overrides device screen dimensions and emulates viewport. When `:mobile` is
   * :width `Integer`, viewport width. `0` by default
   * :height `Integer`, viewport height. `0` by default
   * :scale_factor `Float`, device scale factor. `0` by default
-  * :mobile `Boolean`, whether to emulate mobile device and enable touch. `false` by default
+  * :mobile `Boolean | nil`, `true` emulates a mobile device with touch, `false` a desktop without touch, `nil` a
+    desktop and leaves touch emulation as is. `nil` by default
 
 ```ruby
 page.set_viewport(width: 1000, height: 600, scale_factor: 3)
@@ -29,3 +30,7 @@ size preset:
 ```ruby
 page.set_viewport(mobile: true)
 ```
+
+Turning touch emulation off with `mobile: false` makes Chrome reset hover and pointer media features to the
+detected input devices, which undoes `--blink-settings` overrides such as `primaryHoverType` until the next
+navigation. Leave `:mobile` out unless the page was switched to mobile before.

lib/ferrum/page.rb

@@ -191,22 +191,20 @@ def close_connection
     #
     # @param [Float] scale_factor device scale factor value. 0 disables the override
     #
-    # @param [Boolean] mobile whether to emulate mobile device and enable touch
+    # @param [Boolean, nil] mobile `true` emulates a mobile device with touch, `false` a desktop without touch, `nil`
+    #   a desktop and leaves touch emulation as is. Turning touch off resets hover and pointer to the detected input
+    #   devices, which undoes `--blink-settings` overrides until the next navigation
     #
-    def set_viewport(width: 0, height: 0, scale_factor: 0, mobile: false)
-      command(
-        "Emulation.setTouchEmulationEnabled",
-        enabled: mobile,
-        maxTouchPoints: 1
-      )
+    def set_viewport(width: 0, height: 0, scale_factor: 0, mobile: nil)
+      command("Emulation.setTouchEmulationEnabled", enabled: mobile, maxTouchPoints: 1) unless mobile.nil?
 
       command(
         "Emulation.setDeviceMetricsOverride",
         slowmoable: true,
         width: width,
         height: height,
         deviceScaleFactor: scale_factor,
-        mobile: mobile
+        mobile: mobile || false
       )
     end
 

sig/ferrum/page.rbs

@@ -57,7 +57,7 @@ module Ferrum
 
     def close_connection: () -> void
 
-    def set_viewport: (?width: ::Integer, ?height: ::Integer, ?scale_factor: ::Float, ?mobile: bool) -> Hash[String, untyped]
+    def set_viewport: (?width: ::Integer, ?height: ::Integer, ?scale_factor: ::Float, ?mobile: bool?) -> Hash[String, untyped]
 
     def resize: (?width: ::Numeric?, ?height: ::Numeric?, ?fullscreen: bool) -> Hash[String, untyped]
 

spec/page_spec.rb

@@ -305,6 +305,32 @@ def is_mobile?
         end.not_to(change { is_mobile? })
       end
     end
+
+    context "when mobile is not given" do
+      it "keeps the pointer type set with --blink-settings", :launch do
+        browser = Ferrum::Browser.new(browser_options: { "blink-settings" => "primaryPointerType=2,availablePointerTypes=2" })
+        browser.go_to(base_url)
+
+        expect do
+          browser.set_viewport(width: 500, height: 300)
+        end.not_to(change { browser.evaluate("matchMedia('(pointer: coarse)').matches") }.from(true))
+      ensure
+        browser&.quit
+      end
+    end
+
+    context "when mobile was true before" do
+      it "disables touch/mobile emulation again" do
+        page.go_to("/")
+        page.set_viewport(mobile: true)
+        page.reload
+
+        expect do
+          page.set_viewport(mobile: false)
+          page.reload
+        end.to change { is_mobile? }.from(true).to(false)
+      end
+    end
   end
 
   describe "#on" do