barcodes 0.2.2

# Changelog

All notable changes to this project are documented here. The format is based on
[Keep a Changelog](https://keepachangelog.com/), and this project adheres to
[Semantic Versioning](https://semver.org/) (with `0.x` minor bumps signalling
breaking changes).

## [0.2.2] — 2026-07-23

### Changed

- **Fully fluid SVG.** The generated `<svg>` no longer sets fixed `width`/`height`
  attributes — only a `viewBox` (plus `style="max-width:100%;height:auto"`) — so it
  has no intrinsic pixel size and scales to fill its container's width while
  preserving aspect ratio. This refines the 0.2.1 behavior (which kept the intrinsic
  size and only shrank). Callers wanting a fixed size set it via CSS or a wrapper,
  e.g. `svg { width: 300px; height: auto; }`.

## [0.2.1] — 2026-07-23

### Added

- **Responsive SVG output.** Every generated `<svg>` now carries
  `style="max-width:100%;height:auto"` alongside its `viewBox`, so the symbol
  keeps its intrinsic size but scales down to fit a narrower container while
  preserving aspect ratio. Override with CSS (`svg { width: 100%; height: auto; }`)
  to grow into wider containers.

### Docs

- Document that QR Code is usable through the uniform
  [`BarcodeEncoder::encode_into`](https://docs.rs/barcodes/latest/barcodes/common/traits/trait.BarcodeEncoder.html)
  API (with default ECC/version/mask), in addition to `QrCode::encode_text`.

### Packaging

- Exclude `.github/` from the published crate.

## [0.2.0] — 2026-07-07

### Breaking

- **Zero-allocation core.** The primary API is now
  [`BarcodeEncoder::encode_into(input, &mut [bool])`](https://docs.rs/barcodes/latest/barcodes/common/traits/trait.BarcodeEncoder.html),
  which writes a symbol's modules into a caller-provided buffer and returns an
  `Encoded { Linear | Matrix }` describing the written region. The crate is now
  pure `no_std` with **no heap allocation** by default.
- The owned-output convenience methods `encode()` (returning `BarcodeOutput`)
  and `to_svg_string()` moved behind the new **`alloc`** feature. Code that
  called `Encoder::encode(...)` on 0.1.x must either enable `features = ["alloc"]`
  or migrate to `encode_into`. See [Migration](#migration-from-01x) below.
- `EncodeError` messages are now `&'static str` (no allocated `String`).

### Added

- Feature flags: `alloc` (owned output + SVG string), `std` (implies `alloc`),
  `image` (implies `std`, raster PNG/GIF/WebP output).
- Full-spec, scanner-verified rewrites of the larger symbologies:
  - **PDF417** (ISO/IEC 15438) — byte compaction + Reed–Solomon EC.
  - **GS1 DataBar Omnidirectional / RSS-14** (ISO/IEC 24724).
  - **Aztec Code** (ISO/IEC 24778) — Binary Shift, Reed–Solomon over
    GF(16/64/256/1024).
  - **USPS Intelligent Mail (IMb)** — verified bit-for-bit against the canonical
    USPS-B-3200 DAFT reference vector.
  - **Royal Mail RM4SCC** — 4-state 3-row output.
- Streaming SVG rendering into any `core::fmt::Write` sink via `common::svg`.

### Fixed

- **Data Matrix** ECC 200 now produces scannable symbols, with 32×32–48×48
  multi-region support for larger data.
- **EAN-13/EAN-8 L-code**, **UPC-E parity**, and the **Code 39** pattern table
  corrected (symbols now scan).
- **GS1-128** now decodes correctly (Code B path).
- **UPC-A / UPC-E check digit** for odd-length data (also released as 0.1.3).

### Packaging

- `examples/` and locally generated barcodes are excluded from the published
  crate.

## [0.1.3] — 2026-07-07

### Fixed

- **UPC-A / UPC-E check digit.** The shared check-digit routine weighted digits
  from the left, which is only correct for even-length data (EAN-13's 12
  digits). For UPC-A and UPC-E (11 data digits) the rightmost digit received the
  wrong weight, producing an invalid check digit — UPC-A symbols failed to scan.
  It now weights from the right (the length-independent GS1 rule); EAN-13/EAN-8
  output is unchanged.

## [0.1.2] — 2026

### Fixed

- Critical **EAN-13 / EAN-8 / UPC-E** encoding fixes (L-code digits and UPC-E
  parity) so retail symbols scan.
- **GS1-128** decoding correctness.

## [0.1.1] — 2026

### Fixed

- Data Matrix capacity/length handling and scannability improvements.

## [0.1.0] — 2026

- Initial release: QR, EAN-13/8, UPC-A/E, Code 128/39/93, Codabar, ITF, GS1-128,
  GS1 DataBar, PDF417, Data Matrix, Aztec, USPS IMb, Royal Mail RM4SCC.

## Migration from 0.1.x

**0.1.x (owned output):**

```rust
use barcodes::common::traits::BarcodeEncoder;
use barcodes::ean_upc::ean13::Ean13;

let svg = Ean13::encode("5901234123457").unwrap().to_svg_string();
```

**0.2.0, option A — keep the convenience API** (enable `alloc`):

```toml
barcodes = { version = "0.2", features = ["alloc"] }
```

```rust
// identical code — encode() and to_svg_string() require the `alloc` feature
let svg = Ean13::encode("5901234123457").unwrap().to_svg_string();
```

**0.2.0, option B — zero allocation** (default, no features):

```rust
use barcodes::common::traits::BarcodeEncoder;
use barcodes::common::types::Encoded;
use barcodes::ean_upc::ean13::Ean13;

let mut buf = [false; 128]; // one bool per module
let Encoded::Linear { len, .. } = Ean13::encode_into("5901234123457", &mut buf).unwrap()
else { unreachable!() };
let bars = &buf[..len]; // true = dark module
```

[0.2.2]: https://github.com/ashaffah/barcodes/compare/v0.2.1...v0.2.2
[0.2.1]: https://github.com/ashaffah/barcodes/compare/v0.2.0...v0.2.1
[0.2.0]: https://github.com/ashaffah/barcodes/compare/v0.1.3...v0.2.0
[0.1.3]: https://github.com/ashaffah/barcodes/compare/v0.1.2...v0.1.3
[0.1.2]: https://github.com/ashaffah/barcodes/compare/v0.1.1...v0.1.2
[0.1.1]: https://github.com/ashaffah/barcodes/compare/v0.1.0...v0.1.1
[0.1.0]: https://github.com/ashaffah/barcodes/releases/tag/v0.1.0