Tweak debug logging

1 - Add a log_level build option to control the default log level from
    the build (e.g. -Dlog_level=debug). Defaults to info

2 - Add a new boolean log_unknown_properties build option to enable
    logging unknown properties. Defautls to false.

3 - Remove the log debug for script eval - this can be a huge value
    (i.e. hundreds of KB), which makes the debug log unusable IMO.

build.zig

@@ -44,6 +44,18 @@ pub fn build(b: *std.Build) !void {
         b.option([]const u8, "git_commit", "Current git commit") orelse "dev",
     );
 
+    opts.addOption(
+        std.log.Level,
+        "log_level",
+        b.option(std.log.Level, "log_level", "The log level") orelse std.log.Level.info,
+    );
+
+    opts.addOption(
+        bool,
+        "log_unknown_properties",
+        b.option(bool, "log_unknown_properties", "Log access to unknown properties") orelse false,
+    );
+
     const target = b.standardTargetOptions(.{});
     const optimize = b.standardOptimizeOption(.{});
 
@@ -175,7 +187,7 @@ fn common(b: *std.Build, opts: *std.Build.Step.Options, step: *std.Build.Step.Co
         else => {},
     }
 
-    mod.addImport("build_info", opts.createModule());
+    mod.addImport("build_config", opts.createModule());
     mod.addObjectFile(mod.owner.path(lib_path));
 }
 

src/browser/page.zig

@@ -647,11 +647,7 @@ pub const Page = struct {
                 }
                 return error.JsErr;
             };
-
-            if (builtin.mode == .Debug) {
-                const msg = try res.toString(page.arena);
-                log.debug("eval script {s}: {s}", .{ src, msg });
-            }
+            _ = res;
 
             if (self.onload) |onload| {
                 _ = page.scope.exec(onload, "script_on_load") catch {

src/main.zig

@@ -25,14 +25,14 @@ const App = @import("app.zig").App;
 const Platform = @import("runtime/js.zig").Platform;
 const Browser = @import("browser/browser.zig").Browser;
 
+const build_config = @import("build_config");
 const parser = @import("browser/netsurf.zig");
-const version = @import("build_info").git_commit;
 
 const log = std.log.scoped(.cli);
 
 pub const std_options = std.Options{
     // Set the log level to info
-    .log_level = .info,
+    .log_level = @enumFromInt(@intFromEnum(build_config.log_level)),
 
     // Define logFn to override the std implementation
     .logFn = logFn,
@@ -59,7 +59,7 @@ pub fn main() !void {
             return std.process.cleanExit();
         },
         .version => {
-            std.debug.print("{s}\n", .{version});
+            std.debug.print("{s}\n", .{build_config.git_commit});
             return std.process.cleanExit();
         },
         else => {},

src/runtime/js.zig

@@ -1407,6 +1407,9 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
 
         fn generateNamedIndexer(comptime Struct: type, template_proto: v8.ObjectTemplate) void {
             if (@hasDecl(Struct, "named_get") == false) {
+                if (comptime @import("build_config").log_unknown_properties) {
+                    generateDebugNamedIndexer(Struct, template_proto);
+                }
                 return;
             }
             const configuration = v8.NamedPropertyHandlerConfiguration{
@@ -1441,6 +1444,31 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
             template_proto.setNamedProperty(configuration, null);
         }
 
+        fn generateDebugNamedIndexer(comptime Struct: type, template_proto: v8.ObjectTemplate) void {
+            const configuration = v8.NamedPropertyHandlerConfiguration{
+                .getter = struct {
+                    fn callback(c_name: ?*const v8.C_Name, raw_info: ?*const v8.C_PropertyCallbackInfo) callconv(.c) u8 {
+                        const info = v8.PropertyCallbackInfo.initFromV8(raw_info);
+                        const isolate = info.getIsolate();
+                        const context = isolate.getCurrentContext();
+
+                        const scope: *Scope = @ptrFromInt(context.getEmbedderData(1).castTo(v8.BigInt).getUint64());
+
+                        const property = valueToString(scope.call_arena, .{ .handle = c_name.? }, isolate, context) catch "???";
+                        log.debug("unknwon named property {s}.{s}", .{ @typeName(Struct), property });
+                        return v8.Intercepted.No;
+                    }
+                }.callback,
+
+                // This is really cool. Without this, we'd intercept _all_ properties
+                // even those explicitly set. So, node.length for example would get routed
+                // to our `named_get`, rather than a `get_length`. This might be
+                // useful if we run into a type that we can't model properly in Zig.
+                .flags = v8.PropertyHandlerFlags.OnlyInterceptStrings | v8.PropertyHandlerFlags.NonMasking,
+            };
+            template_proto.setNamedProperty(configuration, null);
+        }
+
         fn generateUndetectable(comptime Struct: type, template: v8.ObjectTemplate) void {
             const has_js_call_as_function = @hasDecl(Struct, "jsCallAsFunction");
 

src/telemetry/lightpanda.zig

@@ -1,6 +1,6 @@
 const std = @import("std");
 const builtin = @import("builtin");
-const build_info = @import("build_info");
+const build_config = @import("build_config");
 
 const Thread = std.Thread;
 const Allocator = std.mem.Allocator;
@@ -151,7 +151,7 @@ const LightPandaEvent = struct {
         try writer.write(builtin.cpu.arch);
 
         try writer.objectField("version");
-        try writer.write(build_info.git_commit);
+        try writer.write(build_config.git_commit);
 
         try writer.objectField("event");
         try writer.write(@tagName(std.meta.activeTag(self.event)));