Module parity 

Measure driven browsers against the same binary started by hand.

The environment reference is a plain command-stream child with no CDP endpoint. Both reference and candidate load the same loopback probe page and POST their reports. A separate reference launch reads chrome://version with a fixed debugging port to capture switches Chrome appends itself.

Structs

ChangedSwitch

A switch whose value changed.

CommandLineComparison

Browser-reported command-line comparison, compatible with JS and Python.

FeatureComparison

Values of a comma-separated feature switch, sorted for comparison.

MeasureParityOptions

Options for native browser parity measurement.

ParityBrowser

Browser metadata in the portable parity report.

ParityCommandLine

Browser-reported command lines and their comparison.

ParityContext

Context used to explain probe differences without hiding unknown changes.

ParityDifference

An explained difference in the portable parity report.

ParityReport

Typed report serialized identically to JavaScript/Python measureParity.

ProbeDifference

One unequal probe value. Missing properties are represented as JSON null.

Constants

PROBE_SOURCE

Canonical environment probe, embedded so crates.io installs need no npm package.

Functions

build_reference_args

Arguments for a plain reference browser, with no implicit automation or CDP switches.

classify_differences

Tag differences using the shared catalogue and return the unexplained subset.

compare_command_lines

Compare reported switch presence and values, including engine feature lists.

diff_reports

Deep-diff objects in sorted key order. Arrays and scalars compare whole. Missing values remain distinct from present JSON null while comparing.

measure_parity

Launch and measure a browser, then close it and remove its owned temporary profile.

measure_session_parity

Measure an existing session without closing it. Navigation goes to the probe page. The caller remains responsible for closing the supplied browser.

parse_switch_args

Parse exact argv entries into switch names and optional values.

parse_switches

Parse the space-joined command line shown by chrome://version. Profile paths containing spaces are regrouped until the next switch.

read_browser_version_page

Read version metadata from a fresh tab, leaving the measured page untouched.