# insta-fun
SVG & WAV snapshot testing for FunDSP audio units.
Generate visual snapshots of audio processing units to catch regressions and verify signal behavior.

> **Note:** Snapshot assertion uses `insta::assert_binary_snapshot` which is currently marked experimental.
## Usage
```rust
use insta_fun::prelude::*;
use fundsp::prelude::*;
#[test]
fn example_test() {
// Simple SVG snapshot (default output_mode = SvgChart)
let unit = sine_hz::<f32>(440.0);
let svg_bytes = snapshot_audio_unit(unit);
// With input signal (impulse)
let filter = lowpass_hz(1000.0, 1.0);
let svg_bytes_with_input = snapshot_audio_unit_with_input(filter, InputSource::impulse());
// Custom chart configuration (SvgChartConfig separated from SnapshotConfig)
let chart = SvgChartConfigBuilder::default()
.chart_title("Custom Sine")
.show_grid(true)
.build()
.unwrap();
let config = SnapshotConfigBuilder::default()
.num_samples(2048)
.output_mode(chart) // inject chart config
.build()
.unwrap();
let custom_svg = snapshot_audio_unit_with_options(sine_hz::<f32>(440.0), config);
// WAV output (audible snapshot)
let wav_config = SnapshotConfigBuilder::default()
.num_samples(2048)
.output_mode(WavOutput::Wav16) // or WavOutput::Wav32
.build()
.unwrap();
let wav_bytes = snapshot_audio_unit_with_input_and_options(sine_hz::<f32>(440.0), InputSource::None, wav_config);
// Macro (produces both an SVG and a 16-bit WAV by default)
assert_audio_unit_snapshot!(sine_hz::<f32>(440.0));
// Macro with custom config (single output based on config.output_mode)
let wav_only_cfg = SnapshotConfigBuilder::default()
.output_mode(WavOutput::Wav32)
.build()
.unwrap();
assert_audio_unit_snapshot!(sine_hz::<f32>(220.0), wav_only_cfg);
}
```
## Features
- Visualizes audio unit inputs and outputs as SVG waveforms
- Generates audible WAV snapshots (16-bit & 32-bit)
- Supports multi-channel audio with color-coded traces
- Configurable sample count, processing mode, warmup, and abnormal sample handling
- Separate chart configuration via SvgChartConfigBuilder
- Built-in input generators (impulse, sine, custom, generator fn, unit passthrough)
- Tick or batch processing (up to fundsp::MAX_BUFFER_SIZE)
- Multiple chart layouts & label formatting options
- Assertion macro (default: both SVG + WAV16 when no custom config)
## Configuration Overview
SnapshotConfig controls audio generation parameters (sample_rate, num_samples, processing_mode, warm_up, allow_abnormal_samples, output_mode).
SvgChartConfig controls purely visual/chart properties (layout, titles, labels, colors, dimensions, etc) and is injected through `SnapshotConfigBuilder::output_mode(chart_cfg)`.
Set WAV output by providing `output_mode(WavOutput::Wav16)` or `output_mode(WavOutput::Wav32)`.
Macro arms without an explicit `SnapshotConfig` produce both an SVG chart (default SvgChartConfig) and a 16-bit WAV file. Arms with a provided `SnapshotConfig` produce exactly one snapshot determined by `output_mode`.
## Processing Modes
- Tick: Process one sample at a time (default) targeting `AudioUnit::tick`
- Batch: Process chunks (<= 64) targeting `AudioUnit::process`
## Examples
See [snapshots](https://github.com/anvlkv/insta-fun/tree/main/src/snapshots) for full list of example charts.
See [tests](https://github.com/anvlkv/insta-fun/tree/main/src/tests.rs) for all usage examples.
### Bonus
Snapshots of all the `fundsp` AudioNodes [anvlkv.github.io/insta-fun](https://anvlkv.github.io/insta-fun)
- Ready-made example suites (charts: 2000 samples; audio: 1 second each):
- Oscillators: cargo run --example oscillators
- Filters (impulse responses): cargo run --example filters
- Time FX, dynamics, and noise: cargo run --example time_fx_and_noise
- Advanced Oscillators (DSF, pulse & PWM): cargo run --example oscillators_advanced
- Advanced Filters (nonlinear & morph progression): cargo run --example filters_advanced
## The Unlicense
See [LICENSE](https://raw.githubusercontent.com/anvlkv/insta-fun/refs/heads/main/LICENSE) file for details.
## P.S.
🩻🎇🏙️🌁
Happy testing!