Fixes browser detection; some refactoring (#737)

* Changed to whitelist graphical browsers.

* Factored out flamegraph_format and generate_html.

* Fixed Windows browser name.

scalene/find_browser.py

@@ -3,15 +3,18 @@
 
 def find_browser() -> Optional[webbrowser.BaseBrowser]:
     """Find the default browser if possible and if compatible."""
-
-    # Mostly taken from the standard library webbrowser module. Search "console browsers" in there.
-    # In general, a browser belongs on this list of the scalene web GUI doesn't work in it.
-    # See https://github.com/plasma-umass/scalene/issues/723.
-    incompatible_browsers = {"www-browser", "links", "elinks", "lynx", "w3m", "links2", "links-g"}
-
+    # Names of known graphical browsers as per Python's webbrowser documentation
+    graphical_browsers = ["windowsdefault", "macosx", "safari", "google-chrome", 
+                          "chrome", "chromium", "firefox", "opera", "edge", "mozilla", "netscape"]
     try:
+        # Get the default browser object
         browser = webbrowser.get()
+        # Check if the browser's class name matches any of the known graphical browsers
+        browser_class_name = str(type(browser)).lower()
+        if any(graphical_browser in browser_class_name for graphical_browser in graphical_browsers):
+            return browser
+        else:
+            return None
     except webbrowser.Error:
+        # Return None if there is an error in getting the browser
         return None
-
-    return None if browser.name in incompatible_browsers else browser

scalene/scalene_profiler.py

@@ -47,7 +47,6 @@
 from collections import defaultdict
 from importlib.abc import SourceLoader
 from importlib.machinery import ModuleSpec
-from jinja2 import Environment, FileSystemLoader
 from types import CodeType, FrameType
 from typing import (
     Any,
@@ -843,23 +842,11 @@ def cpu_signal_handler(
             if sys.platform == "win32":
                 Scalene.__windows_queue.put(None)
 
-    @staticmethod
-    def flamegraph_format() -> str:
-        """Converts stacks to a string suitable for input to Brendan Gregg's flamegraph.pl script."""
-        output = ""
-        for stk in Scalene.__stats.stacks.keys():
-            for item in stk:
-                (fname, fn_name, lineno) = item
-                output += f"{fname} {fn_name}:{lineno};"
-            output += " " + str(Scalene.__stats.stacks[stk])
-            output += "\n"
-        return output
-
     @staticmethod
     def output_profile(program_args: Optional[List[str]] = None) -> bool:
         """Output the profile. Returns true iff there was any info reported the profile."""
         # sourcery skip: inline-immediately-returned-variable
-        # print(Scalene.flamegraph_format())
+        # print(Scalene.flamegraph_format(Scalene.__stats.stacks))
         if Scalene.__args.json:
             json_output = Scalene.__json.output_profiles(
                 Scalene.__program_being_profiled,
@@ -1611,8 +1598,8 @@ def stop() -> None:
         if Scalene.__args.outfile:
             Scalene.__profile_filename = os.path.join(os.path.dirname(Scalene.__args.outfile),
                                                       os.path.basename(Scalene.__profile_filename))
-        if (
-            Scalene.__args.web
+
+        if (Scalene.__args.web
             and not Scalene.__args.cli
             and not Scalene.__is_child
         ):
@@ -1716,42 +1703,6 @@ def exit_handler() -> None:
         with contextlib.suppress(Exception):
             os.remove(f"/tmp/scalene-malloc-lock{os.getpid()}")
 
-    @staticmethod
-    def generate_html(profile_fname: Filename, output_fname: Filename) -> None:
-        """Apply a template to generate a single HTML payload containing the current profile."""
-
-        try:
-            # Load the profile
-            profile_file = pathlib.Path(profile_fname)
-            profile = profile_file.read_text()
-        except FileNotFoundError:
-            return
-
-        # Load the GUI JavaScript file.
-        scalene_dir = os.path.dirname(__file__)
-        gui_fname = os.path.join(scalene_dir, "scalene-gui", "scalene-gui.js")
-        gui_file = pathlib.Path(gui_fname)
-        gui_js = gui_file.read_text()
-
-        # Put the profile and everything else into the template.
-        environment = Environment(
-            loader=FileSystemLoader(os.path.join(scalene_dir, "scalene-gui"))
-        )
-        template = environment.get_template("index.html.template")
-        rendered_content = template.render(
-            profile=profile,
-            gui_js=gui_js,
-            scalene_version=scalene_version,
-            scalene_date=scalene_date,
-        )
-
-        # Write the rendered content to the specified output file.
-        try:
-            with open(output_fname, "w", encoding="utf-8") as f:
-                f.write(rendered_content)
-        except OSError:
-            pass
-
     def profile_code(
         self,
         code: str,
@@ -1809,7 +1760,7 @@ def profile_code(
             ):
                 return exit_status
 
-            Scalene.generate_html(
+            generate_html(
                 profile_fname=Scalene.__profile_filename,
                 output_fname=Scalene.__args.outfile if Scalene.__args.outfile else Scalene.__profiler_html,
             )

scalene/scalene_utility.py

@@ -1,5 +1,9 @@
 import inspect
+import os
+import pathlib
 import sys
+
+from jinja2 import Environment, FileSystemLoader
 from types import FrameType
 from typing import (
     Any,
@@ -14,6 +18,7 @@
     Filename,
     LineNumber
 )
+from scalene.scalene_version import scalene_version, scalene_date
 
 # These are here to simplify print debugging, a la C.
 class LineNo:
@@ -87,3 +92,49 @@ def get_fully_qualified_name(frame: FrameType) -> Filename:
             break
         f = f.f_back
     return fn_name
+
+def flamegraph_format(stacks: Dict[Tuple[Any], int]) -> str:
+    """Converts stacks to a string suitable for input to Brendan Gregg's flamegraph.pl script."""
+    output = ""
+    for stk in stacks.keys():
+        for item in stk:
+            (fname, fn_name, lineno) = item
+            output += f"{fname} {fn_name}:{lineno};"
+        output += " " + str(stacks[stk])
+        output += "\n"
+    return output
+
+def generate_html(profile_fname: Filename, output_fname: Filename) -> None:
+    """Apply a template to generate a single HTML payload containing the current profile."""
+
+    try:
+        # Load the profile
+        profile_file = pathlib.Path(profile_fname)
+        profile = profile_file.read_text()
+    except FileNotFoundError:
+        return
+
+    # Load the GUI JavaScript file.
+    scalene_dir = os.path.dirname(__file__)
+    gui_fname = os.path.join(scalene_dir, "scalene-gui", "scalene-gui.js")
+    gui_file = pathlib.Path(gui_fname)
+    gui_js = gui_file.read_text()
+
+    # Put the profile and everything else into the template.
+    environment = Environment(
+        loader=FileSystemLoader(os.path.join(scalene_dir, "scalene-gui"))
+    )
+    template = environment.get_template("index.html.template")
+    rendered_content = template.render(
+        profile=profile,
+        gui_js=gui_js,
+        scalene_version=scalene_version,
+        scalene_date=scalene_date,
+    )
+
+    # Write the rendered content to the specified output file.
+    try:
+        with open(output_fname, "w", encoding="utf-8") as f:
+            f.write(rendered_content)
+    except OSError:
+        pass