Utilities for screenshot-based testing assertions. More...

#include <screenshot_assertion.h>

Collaboration diagram for yaze::test::ScreenshotAssertion:

Public Types
using	CaptureCallback

Public Member Functions
	ScreenshotAssertion ()

	~ScreenshotAssertion ()=default

void	SetConfig (const ComparisonConfig &config)

const ComparisonConfig &	GetConfig () const

void	SetCaptureCallback (CaptureCallback callback)

absl::StatusOr< ComparisonResult >	AssertMatchesReference (const std::string &reference_path)
	Assert current screen matches a reference image file.

absl::StatusOr< ComparisonResult >	AssertMatchesScreenshot (const Screenshot &expected)
	Assert current screen matches another Screenshot object.

absl::StatusOr< ComparisonResult >	AssertRegionMatches (const std::string &reference_path, const ScreenRegion &region)
	Assert a specific region matches reference.

absl::StatusOr< ComparisonResult >	AssertChanged (const std::string &baseline_name)
	Assert screen has changed since baseline.

absl::StatusOr< ComparisonResult >	AssertUnchanged (const std::string &baseline_name)
	Assert screen has NOT changed since baseline.

absl::Status	CaptureBaseline (const std::string &name)
	Capture and store a baseline screenshot.

absl::Status	SaveAsReference (const std::string &path)
	Save current screen as a new reference image.

absl::StatusOr< Screenshot >	LoadReference (const std::string &path)
	Load a reference image from file.

absl::StatusOr< Screenshot >	GetBaseline (const std::string &name) const
	Get a previously captured baseline.

void	ClearBaselines ()
	Clear all captured baselines.

ComparisonResult	Compare (const Screenshot &actual, const Screenshot &expected)
	Compare two screenshots.

ComparisonResult	CompareRegion (const Screenshot &actual, const Screenshot &expected, const ScreenRegion &region)
	Compare specific regions of two screenshots.

absl::StatusOr< std::string >	GenerateDiffImage (const Screenshot &actual, const Screenshot &expected, const std::string &output_path)
	Generate a visual diff image.

absl::StatusOr< bool >	AssertPixelColor (int x, int y, uint8_t r, uint8_t g, uint8_t b, int tolerance=10)
	Assert pixel at (x, y) has expected color.

absl::StatusOr< bool >	AssertRegionContainsColor (const ScreenRegion &region, uint8_t r, uint8_t g, uint8_t b, float min_coverage=0.1f)
	Assert region contains a specific color.

absl::StatusOr< bool >	AssertRegionExcludesColor (const ScreenRegion &region, uint8_t r, uint8_t g, uint8_t b, int tolerance=10)
	Assert region does NOT contain a specific color.

absl::StatusOr< Screenshot >	CaptureScreen ()
	Capture current screen and return it.

Static Public Member Functions
static absl::Status	SaveScreenshot (const Screenshot &screenshot, const std::string &path)
	Save screenshot to file (PNG format).

static absl::StatusOr< Screenshot >	LoadScreenshot (const std::string &path)
	Load screenshot from file.

Private Member Functions
ComparisonResult	ComparePixelExact (const Screenshot &actual, const Screenshot &expected, const ScreenRegion &region)

ComparisonResult	ComparePerceptualHash (const Screenshot &actual, const Screenshot &expected)

ComparisonResult	CompareStructural (const Screenshot &actual, const Screenshot &expected)

bool	ColorsMatch (uint8_t r1, uint8_t g1, uint8_t b1, uint8_t r2, uint8_t g2, uint8_t b2, int threshold) const

std::vector< ScreenRegion >	FindDifferingRegions (const Screenshot &actual, const Screenshot &expected, int threshold)

Private Attributes
ComparisonConfig	config_

CaptureCallback	capture_callback_

std::unordered_map< std::string, Screenshot >	baselines_

Detailed Description

Utilities for screenshot-based testing assertions.

Provides tools for capturing, comparing, and asserting screenshot content for visual regression testing and AI-assisted verification.

Usage:

ScreenshotAssertion assertion;
assertion.SetCaptureCallback(my_capture_func);
 
// Compare to reference
auto result = assertion.AssertMatchesReference("expected_state.png");
EXPECT_TRUE(result.passed) << result.error_message;
 
// Compare specific regions
auto result = assertion.AssertRegionMatches(
    "canvas_expected.png",
    ScreenRegion::At(100, 100, 256, 256));
 
// Check for visual changes
assertion.CaptureBaseline("before_edit");
// ... make changes ...
auto result = assertion.AssertChanged("before_edit");

Definition at line 121 of file screenshot_assertion.h.

Member Typedef Documentation

◆ CaptureCallback

using yaze::test::ScreenshotAssertion::CaptureCallback

Initial value:

std::function<absl::StatusOr<Screenshot>()>

Definition at line 131 of file screenshot_assertion.h.

Constructor & Destructor Documentation

◆ ScreenshotAssertion()

yaze::test::ScreenshotAssertion::ScreenshotAssertion ( )

default

◆ ~ScreenshotAssertion()

yaze::test::ScreenshotAssertion::~ScreenshotAssertion ( )

default

Member Function Documentation

◆ SetConfig()

void yaze::test::ScreenshotAssertion::SetConfig ( const ComparisonConfig & config )

inline

Definition at line 127 of file screenshot_assertion.h.

References config_.

◆ GetConfig()

const ComparisonConfig & yaze::test::ScreenshotAssertion::GetConfig ( ) const

inline

Definition at line 128 of file screenshot_assertion.h.

References config_.

◆ SetCaptureCallback()

void yaze::test::ScreenshotAssertion::SetCaptureCallback ( CaptureCallback callback )

inline

Definition at line 133 of file screenshot_assertion.h.

References capture_callback_.

◆ AssertMatchesReference()

absl::StatusOr< ComparisonResult > yaze::test::ScreenshotAssertion::AssertMatchesReference ( const std::string & reference_path )

Assert current screen matches a reference image file.

Definition at line 15 of file screenshot_assertion.cc.

References CaptureScreen(), Compare(), config_, LoadReference(), and yaze::test::ComparisonConfig::tolerance.

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◆ AssertMatchesScreenshot()

absl::StatusOr< ComparisonResult > yaze::test::ScreenshotAssertion::AssertMatchesScreenshot ( const Screenshot & expected )

Assert current screen matches another Screenshot object.

Definition at line 33 of file screenshot_assertion.cc.

References CaptureScreen(), Compare(), config_, and yaze::test::ComparisonConfig::tolerance.

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◆ AssertRegionMatches()

absl::StatusOr< ComparisonResult > yaze::test::ScreenshotAssertion::AssertRegionMatches	(	const std::string &	reference_path,
		const ScreenRegion &	region )

Assert a specific region matches reference.

Definition at line 46 of file screenshot_assertion.cc.

References CaptureScreen(), CompareRegion(), config_, LoadReference(), and yaze::test::ComparisonConfig::tolerance.

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◆ AssertChanged()

absl::StatusOr< ComparisonResult > yaze::test::ScreenshotAssertion::AssertChanged ( const std::string & baseline_name )

Assert screen has changed since baseline.

Definition at line 64 of file screenshot_assertion.cc.

References CaptureScreen(), Compare(), config_, GetBaseline(), and yaze::test::ComparisonConfig::tolerance.

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◆ AssertUnchanged()

absl::StatusOr< ComparisonResult > yaze::test::ScreenshotAssertion::AssertUnchanged ( const std::string & baseline_name )

Assert screen has NOT changed since baseline.

Definition at line 83 of file screenshot_assertion.cc.

References CaptureScreen(), Compare(), config_, GetBaseline(), and yaze::test::ComparisonConfig::tolerance.

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◆ CaptureBaseline()

absl::Status yaze::test::ScreenshotAssertion::CaptureBaseline ( const std::string & name )

Capture and store a baseline screenshot.

Definition at line 101 of file screenshot_assertion.cc.

References baselines_, CaptureScreen(), and LOG_DEBUG.

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◆ SaveAsReference()

absl::Status yaze::test::ScreenshotAssertion::SaveAsReference ( const std::string & path )

Save current screen as a new reference image.

Definition at line 114 of file screenshot_assertion.cc.

References CaptureScreen(), and SaveScreenshot().

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◆ LoadReference()

absl::StatusOr< Screenshot > yaze::test::ScreenshotAssertion::LoadReference ( const std::string & path )

Load a reference image from file.

Definition at line 123 of file screenshot_assertion.cc.

References LoadScreenshot().

Referenced by AssertMatchesReference(), and AssertRegionMatches().

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◆ GetBaseline()

absl::StatusOr< Screenshot > yaze::test::ScreenshotAssertion::GetBaseline ( const std::string & name ) const

Get a previously captured baseline.

Definition at line 128 of file screenshot_assertion.cc.

References baselines_.

Referenced by AssertChanged(), and AssertUnchanged().

◆ ClearBaselines()

void yaze::test::ScreenshotAssertion::ClearBaselines ( )

inline

Clear all captured baselines.

Definition at line 195 of file screenshot_assertion.h.

References baselines_.

◆ Compare()

ComparisonResult yaze::test::ScreenshotAssertion::Compare	(	const Screenshot &	actual,
		const Screenshot &	expected )

Compare two screenshots.

Definition at line 138 of file screenshot_assertion.cc.

References CompareRegion(), and yaze::test::ScreenRegion::FullScreen().

Referenced by AssertChanged(), AssertMatchesReference(), AssertMatchesScreenshot(), and AssertUnchanged().

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◆ CompareRegion()

ComparisonResult yaze::test::ScreenshotAssertion::CompareRegion	(	const Screenshot &	actual,
		const Screenshot &	expected,
		const ScreenRegion &	region )

◆ GenerateDiffImage()

absl::StatusOr< std::string > yaze::test::ScreenshotAssertion::GenerateDiffImage	(	const Screenshot &	actual,
		const Screenshot &	expected,
		const std::string &	output_path )

Generate a visual diff image.

Definition at line 274 of file screenshot_assertion.cc.

References yaze::test::ComparisonConfig::color_threshold, ColorsMatch(), config_, yaze::test::Screenshot::data, yaze::test::Screenshot::GetPixelIndex(), yaze::test::Screenshot::height, SaveScreenshot(), and yaze::test::Screenshot::width.

Referenced by CompareRegion().

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◆ AssertPixelColor()

absl::StatusOr< bool > yaze::test::ScreenshotAssertion::AssertPixelColor	(	int	x,
		int	y,
		uint8_t	r,
		uint8_t	g,
		uint8_t	b,
		int	tolerance = 10 )

Assert pixel at (x, y) has expected color.

Parameters

x	X coordinate
y	Y coordinate
r	Expected red (0-255)
g	Expected green (0-255)
b	Expected blue (0-255)
tolerance	Per-channel tolerance

Definition at line 325 of file screenshot_assertion.cc.

References CaptureScreen(), and ColorsMatch().

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◆ AssertRegionContainsColor()

absl::StatusOr< bool > yaze::test::ScreenshotAssertion::AssertRegionContainsColor	(	const ScreenRegion &	region,
		uint8_t	r,
		uint8_t	g,
		uint8_t	b,
		float	min_coverage = 0.1f )

Assert region contains a specific color.

Definition at line 341 of file screenshot_assertion.cc.

References CaptureScreen(), yaze::test::ComparisonConfig::color_threshold, ColorsMatch(), config_, yaze::test::ScreenRegion::height, yaze::test::ScreenRegion::width, yaze::test::ScreenRegion::x, and yaze::test::ScreenRegion::y.

Referenced by AssertRegionExcludesColor().

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◆ AssertRegionExcludesColor()

absl::StatusOr< bool > yaze::test::ScreenshotAssertion::AssertRegionExcludesColor	(	const ScreenRegion &	region,
		uint8_t	r,
		uint8_t	g,
		uint8_t	b,
		int	tolerance = 10 )

Assert region does NOT contain a specific color.

Definition at line 371 of file screenshot_assertion.cc.

References AssertRegionContainsColor().

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◆ CaptureScreen()

absl::StatusOr< Screenshot > yaze::test::ScreenshotAssertion::CaptureScreen ( )

Capture current screen and return it.

Definition at line 381 of file screenshot_assertion.cc.

References capture_callback_.

Referenced by AssertChanged(), AssertMatchesReference(), AssertMatchesScreenshot(), AssertPixelColor(), AssertRegionContainsColor(), AssertRegionMatches(), AssertUnchanged(), CaptureBaseline(), and SaveAsReference().

◆ SaveScreenshot()

absl::Status yaze::test::ScreenshotAssertion::SaveScreenshot	(	const Screenshot &	screenshot,
		const std::string &	path )

static

Save screenshot to file (PNG format).

Todo: Implement proper PNG encoding

Definition at line 388 of file screenshot_assertion.cc.

References yaze::test::Screenshot::data, yaze::test::Screenshot::height, LOG_DEBUG, and yaze::test::Screenshot::width.

Referenced by GenerateDiffImage(), and SaveAsReference().

◆ LoadScreenshot()

absl::StatusOr< Screenshot > yaze::test::ScreenshotAssertion::LoadScreenshot ( const std::string & path )

static

Load screenshot from file.

Definition at line 414 of file screenshot_assertion.cc.

References yaze::test::Screenshot::data, yaze::test::Screenshot::height, yaze::test::Screenshot::source, and yaze::test::Screenshot::width.

Referenced by LoadReference().

◆ ComparePixelExact()

ComparisonResult yaze::test::ScreenshotAssertion::ComparePixelExact	(	const Screenshot &	actual,
		const Screenshot &	expected,
		const ScreenRegion &	region )

private

Definition at line 187 of file screenshot_assertion.cc.

References yaze::test::ComparisonConfig::color_threshold, ColorsMatch(), config_, yaze::test::Screenshot::data, yaze::test::ComparisonResult::difference_percentage, yaze::test::ComparisonResult::differing_pixels, yaze::test::Screenshot::GetPixelIndex(), yaze::test::ScreenRegion::height, yaze::test::Screenshot::height, yaze::test::ComparisonConfig::ignore_regions, yaze::test::ComparisonResult::similarity, yaze::test::ComparisonResult::total_pixels, yaze::test::ScreenRegion::width, yaze::test::Screenshot::width, yaze::test::ScreenRegion::x, and yaze::test::ScreenRegion::y.

Referenced by CompareRegion().

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◆ ComparePerceptualHash()

ComparisonResult yaze::test::ScreenshotAssertion::ComparePerceptualHash	(	const Screenshot &	actual,
		const Screenshot &	expected )

private

Todo: Implement proper pHash algorithm

Definition at line 256 of file screenshot_assertion.cc.

References yaze::test::ComparisonResult::error_message.

Referenced by CompareRegion().

◆ CompareStructural()

ComparisonResult yaze::test::ScreenshotAssertion::CompareStructural	(	const Screenshot &	actual,
		const Screenshot &	expected )

private

Todo: Implement proper SSIM algorithm

Definition at line 265 of file screenshot_assertion.cc.

References yaze::test::ComparisonResult::error_message.

Referenced by CompareRegion().

◆ ColorsMatch()

bool yaze::test::ScreenshotAssertion::ColorsMatch	(	uint8_t	r1,
		uint8_t	g1,
		uint8_t	b1,
		uint8_t	r2,
		uint8_t	g2,
		uint8_t	b2,
		int	threshold ) const

private

Definition at line 434 of file screenshot_assertion.cc.

Referenced by AssertPixelColor(), AssertRegionContainsColor(), ComparePixelExact(), and GenerateDiffImage().

◆ FindDifferingRegions()

std::vector< ScreenRegion > yaze::test::ScreenshotAssertion::FindDifferingRegions	(	const Screenshot &	actual,
		const Screenshot &	expected,
		int	threshold )

private

Todo: Implement region clustering for difference visualization

Definition at line 441 of file screenshot_assertion.cc.

Member Data Documentation

◆ config_

ComparisonConfig yaze::test::ScreenshotAssertion::config_

private

Definition at line 269 of file screenshot_assertion.h.

Referenced by AssertChanged(), AssertMatchesReference(), AssertMatchesScreenshot(), AssertRegionContainsColor(), AssertRegionMatches(), AssertUnchanged(), ComparePixelExact(), CompareRegion(), GenerateDiffImage(), GetConfig(), and SetConfig().

◆ capture_callback_

CaptureCallback yaze::test::ScreenshotAssertion::capture_callback_

private

Definition at line 270 of file screenshot_assertion.h.

Referenced by CaptureScreen(), and SetCaptureCallback().

◆ baselines_

std::unordered_map<std::string, Screenshot> yaze::test::ScreenshotAssertion::baselines_

private

Definition at line 271 of file screenshot_assertion.h.

Referenced by CaptureBaseline(), ClearBaselines(), and GetBaseline().

The documentation for this class was generated from the following files:

src/app/test/screenshot_assertion.h
src/app/test/screenshot_assertion.cc

	yaze 0.3.2 Link to the Past ROM Editor

Public Types

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ CaptureCallback

Constructor & Destructor Documentation

◆ ScreenshotAssertion()

◆ ~ScreenshotAssertion()

Member Function Documentation

◆ SetConfig()

◆ GetConfig()

◆ SetCaptureCallback()

◆ AssertMatchesReference()

◆ AssertMatchesScreenshot()

◆ AssertRegionMatches()

◆ AssertChanged()

◆ AssertUnchanged()

◆ CaptureBaseline()

◆ SaveAsReference()

◆ LoadReference()

◆ GetBaseline()

◆ ClearBaselines()

◆ Compare()

◆ CompareRegion()

◆ GenerateDiffImage()

◆ AssertPixelColor()

◆ AssertRegionContainsColor()

◆ AssertRegionExcludesColor()

◆ CaptureScreen()

◆ SaveScreenshot()

◆ LoadScreenshot()

◆ ComparePixelExact()

◆ ComparePerceptualHash()

◆ CompareStructural()

◆ ColorsMatch()

◆ FindDifferingRegions()

Member Data Documentation

◆ config_

◆ capture_callback_

◆ baselines_