#![warn(missing_docs)]

/*!
Lenient parser for Semantic Version numbers.

## Motivation

This crate aims to provide an alternative parser for [semver `Version`s](https://crates.io/crates/semver).

Instead of adhering to the semver specification, this parser is more lenient in what it allows.
The differenc include:

- Minor and Path are optional an default to 0 (e.g. "1" parses as "1.0.0")
- Pre-release identifier may be separated by `.` as well (e.g. "1.2.3.rc1" parses as "1.2.3-rc1")
- Some pre-release identifiers are parsed as build identifier (e.g. "1.2.3.Final" parses as "1.2.3+Final")
- Additional numeric identifiers are parsed as build identifier (e.g "1.2.3.4.5" parses as "1.2.3+4.5")
- A leading `v` or `V` is allowed (e.g. "v1.2.3" parses as "1.2.3")
- Numbers that overflow an u64 are treated as strings (e.g. "1.2.3-9876543210987654321098765432109876543210" parses without error)

This diagram shows lenient parsing grammar

![have a look at doc/railroad.svg](https://knutwalker.s3.eu-central-1.amazonaws.com/lenient-semver/doc/railroad.svg)

## Examples

```rust
# use semver_v100 as semver;
use semver::Version;

let version = lenient_semver::parse("1.2.3");
assert_eq!(version, Ok(Version::new(1, 2, 3)));

// examples of a version that would not be accepted by semver_parser
assert_eq!(
    lenient_semver::parse("1.2.M1").unwrap(),
    Version::parse("1.2.0-M1").unwrap()
);
assert!(Version::parse("1.2.M1").is_err());

assert_eq!(
    lenient_semver::parse("1").unwrap(),
    Version::parse("1.0.0").unwrap()
);
assert!(Version::parse("1").is_err());

assert_eq!(
    lenient_semver::parse("1.2.3.Final").unwrap(),
    Version::parse("1.2.3+Final").unwrap()
);
assert!(Version::parse("1.2.3.Final").is_err());

assert_eq!(
    lenient_semver::parse("1.2.3.4.5").unwrap(),
    Version::parse("1.2.3+4.5").unwrap()
);
assert!(Version::parse("1.2.3.4.5").is_err());

assert_eq!(
    lenient_semver::parse("v1.2.3").unwrap(),
    Version::parse("1.2.3").unwrap()
);
assert!(Version::parse("v1.2.3").is_err());

assert_eq!(
    lenient_semver::parse("1.2.9876543210987654321098765432109876543210").unwrap(),
    Version::parse("1.2.0-9876543210987654321098765432109876543210").unwrap()
);
assert!(Version::parse("1.2.9876543210987654321098765432109876543210").is_err());
```

## Parsing into custom versions

The parser is not fixed on returning a `semver::Version`, it instead parses into a `lenient_semver::VersionBuilder`.
The default features for this crate contain a `VersionBuilder` implementation for `semver::Version`, but any implementation can be used with `parse_into`.

### Examples

```rust
# // This example is replicated in the tests module
# // Please try to keep them in sync
use lenient_semver::VersionBuilder;

/// Simpler version struct that lives only on the stack
#[derive(Debug, Default)]
struct MyVersion {
    numbers: [u64; 3],
    is_pre_release: bool,
}

/// The VersionBuilder trait is generic over the lifetime of the input string.
/// We don't store references to those strings, so we don't care about the specific lifetime.
impl VersionBuilder<'_> for MyVersion {
    /// We will modify the target struct directly
    type Out = Self;

    /// Construct a new builder instance.
    /// One can only expect `set_major` to be called before `build`, all other methods are optional.
    fn new() -> Self {
        Self::default()
    }

    /// Construct the final result. In this case, we can just return ourselves.
    fn build(self) -> Self::Out {
        self
    }

    /// Called when the major component was found.
    fn set_major(&mut self, major: u64) {
        self.numbers[0] = major;
    }

    /// Called when the minor component was found.
    fn set_minor(&mut self, minor: u64) {
        self.numbers[1] = minor;
    }

    /// Called when the patch component was found.
    fn set_patch(&mut self, patch: u64) {
        self.numbers[2] = patch;
    }

    /// Called when any pre-relase metadata identifier was found.
    /// This identifier can just numeric, no attempts at parsing it into a number have been made.
    /// For this implementation, we don't care about the value, just it's presence.
    fn add_pre_release(&mut self, _pre_release: &str) {
        self.is_pre_release = true
    }
}

let input = "1.3.3.7-alpha21+build.42";
let my_version = lenient_semver::parse_into::<MyVersion>(input).unwrap();

assert_eq!([1, 3, 3], my_version.numbers);
assert!(my_version.is_pre_release);
```

The VersionBuilder has empty default implementation for the various methods, making it easy to use it for use-cases beyond just parsing.
The following example implements a function that checks if a given string represents any form of pre-release version.

```rust
# // This example is replicated in the tests module
# // Please try to keep them in sync
use lenient_semver::VersionBuilder;

/// newtype around bool, so we can implement the VersionBuilder trait for it
#[derive(Debug, Default)]
struct IsPreRelease(bool);

impl VersionBuilder<'_> for IsPreRelease {
    /// Here we parse into a different value than Self
    type Out = bool;

    fn new() -> Self {
        Self::default()
    }

    /// Return the wrapped bool
    fn build(self) -> Self::Out {
        self.0
    }

    /// We only care about this method and can ignore all the other ones
    fn add_pre_release(&mut self, _pre_release: &str) {
        self.0 = true;
    }
}

/// This method also return false for invalid version strings,
/// which is technically true, as those are not pre-release versions.
/// Usually you would want to have a better error handling.
fn is_pre_release(v: &str) -> bool {
    lenient_semver::parse_into::<IsPreRelease>(v).unwrap_or_default()
}

assert!(is_pre_release("1.2.3-pre") == true);
assert!(is_pre_release("1.2.3") == false);
assert!(is_pre_release("1.2.3+build") == false);
```

## Features

`lenient_semver` comes with a number of features:


|   feature name | default enabled | transitive dependencies | purpose
| -------------: | --------------- | ----------------------- | --------
|         semver | **yes**         | `semver = "1"`          | Provides `VersionBuilder` implementation for `semver = "1"`.
|      semver011 | no              | `semver = "0.11"`       | Provides `VersionBuilder` implementation for `semver = "0.11"`.
|      semver010 | no              | `semver = "0.10"`       | Provides `VersionBuilder` implementation for `semver = "0.10"`.
|  parse_partial | no              |                         | Provides `parse_partial` method for partially parsing a version from the beginning of a string.
|   version_lite | no              | `lenient_version = "*"` | A custom Version as alternative to `semver::Version` that complements some leneient features, such as additional numbers beyond patch.
| version_semver | no              | `lenient_version = "*"` | Add conversions From `lenient_version` Into `semver::Version`.
|  version_serde | no              | `serde = "1"`           | Serde Deserializer and Serializer implementation for `lenient_version`.


### Examples

#### `semver`

```toml
lenient_semver = { version = "*", features = [ "semver" ] }
```

```rust
# #[cfg(not(feature = "semver"))]
# compile_error!("Please run doc tests with --all-features");
# use semver_v100 as semver;
use semver::Version;

// This features is enabled by default and is usable through `parse` directly.
let version = lenient_semver::parse("v1.2.3.Final").unwrap();
assert_eq!(version, Version::parse("1.2.3+Final").unwrap());

// It can also be used with `parse_into`.
let version = lenient_semver::parse_into::<Version>("v1.2.3.Final").unwrap();
assert_eq!(version, Version::parse("1.2.3+Final").unwrap());
```

#### `semver011`

```toml
lenient_semver = { version = "*", features = [ "semver011" ] }
```

```rust
# #[cfg(not(feature = "semver011"))]
# compile_error!("Please run doc tests with --all-features");
# use semver_v011 as semver;
// Rename is just for demonstration and not required
use semver::Version as Version011;

// The default parse is fixed to the latest semver::Version,
// so we need to use `parse_into`.
let version = lenient_semver::parse_into::<Version011>("v1.2.3.Final").unwrap();
assert_eq!(version, Version011::parse("1.2.3+Final").unwrap());
```

#### `semver010`

```toml
lenient_semver = { version = "*", features = [ "semver010" ] }
```

```rust
# #[cfg(not(feature = "semver010"))]
# compile_error!("Please run doc tests with --all-features");
# use semver_v010 as semver;
// Rename is just for demonstration and not required
use semver::Version as Version010;

// The default parse is fixed to the latest semver::Version,
// so we need to use `parse_into`.
let version = lenient_semver::parse_into::<Version010>("v1.2.3.Final").unwrap();
assert_eq!(version, Version010::parse("1.2.3+Final").unwrap());
```

#### `version_lite`

```toml
lenient_semver = { version = "*", features = [ "version_lite" ] }
```

With this features, lenient_semver now comes with it's own version.
That particular implementation supports numbers beyond patch directly.
Note that lenient_semver still parses those additional number without complaining,
but they are added as build attribute to semver Versions.

```rust
# #[cfg(not(feature = "version_lite"))]
# compile_error!("Please run doc tests with --all-features");
use lenient_semver::Version;

let version = lenient_semver::parse_into::<Version>("1.3.3.7").unwrap();
assert_eq!(version, Version::parse("1.3.3.7").unwrap()); // Version::parse delegates to this parser
```

The native support allows such version to be compared properly, which does not work with semver.

```rust
# #[cfg(not(all(feature = "version_lite", feature = "semver011")))]
# compile_error!("Please run doc tests with --all-features");
# use semver_v011 as semver;
use lenient_semver::Version;

let version_a = Version::parse("1.3.3.7").unwrap();
let version_b = Version::parse("1.3.3.8").unwrap();
assert!(version_a < version_b);

// with semver pre 1.0, that fails:
let version_a = lenient_semver::parse_into::<semver::Version>("1.3.3.7").unwrap();
let version_b = lenient_semver::parse_into::<semver::Version>("1.3.3.8").unwrap();
assert_eq!(version_a < version_b, false);
assert_eq!(version_a, version_b);
```

Furthermore, `Version` does not own the data for the metadata identifiers.
The metadata can be disassociated, so the version can reference a different owner.

```rust
# // This example is replicated in the tests module
# // Please try to keep them in sync
# #[cfg(not(feature = "version_lite"))]
# compile_error!("Please run doc tests with --all-features");
use lenient_semver::{Version, VersionBuilder};

let input = "1.3.3.7-beta.21+build.42";
// make an owned copy, so we don't cheat by using the 'static lifetime.
let input = String::from(input);

// This version references slices from the `input` String
let version = lenient_semver::parse_into::<Version>(input.as_ref()).unwrap();

// Which prevents us from dropping the input
// drop(input);

// We can disassociate the metadata, which allows the new version to reference something else
let (mut version, pre, build) = version.disassociate_metadata();

// We still get the referenced input slices, so we create owned copies
let pre: Option<String> = pre.map(ToOwned::to_owned);
let build: Option<String> = build.map(ToOwned::to_owned);

// now we can safely drop the input
drop(input);

// We can also re-add the cloned identifiers.
// The version would now be bound to the lifetime of this method.
// Just for fun, we swap pre-release and build
if let Some(pre) = pre.as_deref() {
    version.add_build(pre);
}
if let Some(build) = build.as_deref() {
    version.add_pre_release(build);
}

assert_eq!("1.3.3.7-build.42+beta.21".to_string(), version.to_string());
```

#### `version_semver`

```toml
lenient_semver = { version = "*", features = [ "version_semver" ] }
```

If you need to store an owned copy of the version information, you should copy into `semver::Version` or your custom version type instead.
If you only ever intend to store the version information, it might make more sense to parse directly into `semver::Version` instead.

```rust
# #[cfg(all(not(feature = "version_lite"), not(feature = "version_semver")))]
# compile_error!("Please run doc tests with --all-features");
# use semver_v100 as semver;
use semver::Version;

let input = String::from("v1.3.3.7-beta-21+build-42");
let version = lenient_semver::Version::parse(&input).unwrap();
let version = Version::from(version);
assert_eq!("1.3.3-beta-21+7.build-42", &version.to_string());
```

#### `version_serde`

```toml
lenient_semver = { version = "*", features = [ "version_serde" ] }
```

This feature also enabled `version_lite` and brings serde support for the own Version type.
Since `lenient_semver::Version` does not take ownership of the metadata identifiers,
the lifetime of the deserialization result is bound to the input.

```rust
# // This example is replicated in the tests module
# // Please try to keep them in sync
# #[cfg(any(not(feature = "version_lite"), not(feature = "version_serde")))]
# compile_error!("Please run doc tests with --all-features");
use lenient_semver::{Version, VersionBuilder};
use serde::Deserialize;

#[derive(Debug, Deserialize)]
struct DependencySpec<'input> {
    /// Refer to name as owned value
    name: String,
    /// Borrows from the input string
    #[serde(borrow)]
    version: Version<'input>,
}

let input = "
    {
        \"name\": \"lenient_semver\",
        \"version\": \"1.3.3.7+build.42\"
    }";
// make an owned copy, so we don't cheat by using the 'static lifetime.
let input = String::from(input);

// use serde as one would normally do
let dep: DependencySpec = serde_json::from_str(input.as_ref()).unwrap();

// cannot move out of `input` because it is borrowed
// drop(input);

let mut expected = Version::new(1, 3, 3);
expected.add_additional(7);
expected.add_build("build.42");

assert_eq!(dep.version, expected);

// now we can drop the input
drop(input);
```

#### `parse_partial`

```toml
lenient_semver = { version = "*", features = [ "parse_partial" ] }
```

This feature enables the `partial` feature of the parser.
The partial parser will not try to consume all input.
Instead it parses the version as far as possible and will return the unconsumed input alongside the parsed version.

```rust
# // This example is replicated in the tests module
# // Please try to keep them in sync
# #[cfg(not(feature = "parse_partial"))]
# compile_error!("Please run doc tests with --all-features");
use lenient_semver::{Version, VersionBuilder, parser};
let input = "1.2.3   42+build 1.3.3.7 // end";

// parse first version
let (version, remainder) = parser::parse_partial::<Version>(input).unwrap();
let expected = Version::new(1, 2, 3);
assert_eq!(version, expected);
// trailing whitespace is considered part of a version and consumed as well
assert_eq!("42+build 1.3.3.7 // end", remainder);

// parse second version
let (version, remainder) = parser::parse_partial::<Version>(remainder).unwrap();
let mut expected = Version::new(42, 0, 0);
expected.add_build("build");
assert_eq!(version, expected);
assert_eq!("1.3.3.7 // end", remainder);

// parse last version
let (version, remainder) = parser::parse_partial::<Version>(remainder).unwrap();
let mut expected = Version::new(1, 3, 3);
expected.add_additional(7);
assert_eq!(version, expected);
assert_eq!("// end", remainder);

// parse partial still expects to parse something.
// It will fail with `UnexpectedInput` or `MissingMajorNumber` if the input does not match at least a major version.
// let's try to parse the remaining input
let error = parser::parse_partial::<Version>(remainder).unwrap_err();
assert_eq!(error.error_kind(), parser::ErrorKind::UnexpectedInput);
assert_eq!(error.error_line(), "Unexpected `/`");

// or an empty string
let error = parser::parse_partial::<Version>("         ").unwrap_err();
assert_eq!(error.error_kind(), parser::ErrorKind::MissingMajorNumber);
assert_eq!(
    error.error_line(),
    "Could not parse the major identifier: No input"
);

// The rules of when a certain number will be parsed are even more relaxed
let (version, remainder) = parser::parse_partial::<Version>("1foobar").unwrap();
let expected = Version::new(1, 0, 0);
assert_eq!(version, expected);
assert_eq!(remainder, "foobar");

// Furthermore, the characters `*` and `?` are allowed to appear everywhere where other alphabetic character are allowed.
// This relaxes the rule that only a-z, A-Z, and 0-9 are allowed.
// Those characters have no special meaning and will be parsed as pre-release or build segment.
let (version, remainder) = parser::parse_partial::<Version>("1.2.*+final?").unwrap();
let mut expected = Version::new(1, 2, 0);
expected.add_pre_release("*");
expected.add_build("final?");
assert_eq!(version, expected);
assert_eq!(remainder, "");
```
*/

pub use lenient_semver_parser::{self as parser, VersionBuilder};
#[cfg(feature = "version_lite")]
pub use lenient_version::{Version, Version as VersionLite};

/// Parse a string slice into a Version.
///
/// This parser does not require semver-specification conformant input and is more lenient in what it allows.
/// The differenc include:
///
/// - Minor and Path are optional an default to 0 (e.g. "1" parses as "1.0.0")
/// - Pre-release identifier may be separated by `.` as well (e.g. "1.2.3.rc1" parses as "1.2.3-rc1")
/// - Some pre-release identifiers are parsed as build identifier (e.g. "1.2.3.Final" parses as "1.2.3+Final")
/// - Additional numeric identifiers are parsed as build identifier (e.g "1.2.3.4.5" parses as "1.2.3+4.5")
/// - A leading `v` or `V` is allowed (e.g. "v1.2.3" parses as "1.2.3")
/// - Numbers that overflow an u64 are treated as strings (e.g. "1.2.3-9876543210987654321098765432109876543210" parses without error)
///
/// This diagram shows lenient parsing grammar
///
/// ![have a look at doc/railroad.svg](https://knutwalker.s3.eu-central-1.amazonaws.com/lenient-semver/doc/railroad.svg)
///
/// ## Examples
///
/// ```rust
/// # use semver_v100 as semver;;
/// use semver::Version;
///
/// let version = lenient_semver::parse("1.2.3");
/// assert_eq!(version, Ok(Version::new(1, 2, 3)));
///
/// // examples of a version that would not be accepted by semver_parser
/// assert_eq!(
///     lenient_semver::parse("1.2.M1").unwrap(),
///     Version::parse("1.2.0-M1").unwrap()
/// );
/// assert!(Version::parse("1.2.M1").is_err());
///
/// assert_eq!(
///     lenient_semver::parse("1").unwrap(),
///     Version::parse("1.0.0").unwrap()
/// );
/// assert!(Version::parse("1").is_err());
///
/// assert_eq!(
///     lenient_semver::parse("1.2.3.Final").unwrap(),
///     Version::parse("1.2.3+Final").unwrap()
/// );
/// assert!(Version::parse("1.2.3.Final").is_err());
///
/// assert_eq!(
///     lenient_semver::parse("1.2.3.4.5").unwrap(),
///     Version::parse("1.2.3+4.5").unwrap()
/// );
/// assert!(Version::parse("1.2.3.4.5").is_err());
///
/// assert_eq!(
///     lenient_semver::parse("v1.2.3").unwrap(),
///     Version::parse("1.2.3").unwrap()
/// );
/// assert!(Version::parse("v1.2.3").is_err());
///
/// assert_eq!(
///     lenient_semver::parse("1.2.9876543210987654321098765432109876543210").unwrap(),
///     Version::parse("1.2.0-9876543210987654321098765432109876543210").unwrap()
/// );
/// assert!(Version::parse("1.2.9876543210987654321098765432109876543210").is_err());
/// ```
///
/// This method is fixed to return a [`semver_v100::Version`].
/// A more flexible variant is [`parse_into`].
#[cfg(feature = "semver")]
pub fn parse(input: &str) -> Result<semver_v100::Version, parser::Error> {
    parser::parse::<semver_v100::Version>(input)
}

/// Parse a string slice into a Version.
///
/// This parser does not require semver-specification conformant input and is more lenient in what it allows.
/// The differenc include:
///
/// - Minor and Path are optional an default to 0 (e.g. "1" parses as "1.0.0")
/// - Pre-release identifier may be separated by `.` as well (e.g. "1.2.3.rc1" parses as "1.2.3-rc1")
/// - Some pre-release identifiers are parsed as build identifier (e.g. "1.2.3.Final" parses as "1.2.3+Final")
/// - Additional numeric identifiers are parsed as build identifier (e.g "1.2.3.4.5" parses as "1.2.3+4.5")
/// - A leading `v` or `V` is allowed (e.g. "v1.2.3" parses as "1.2.3")
/// - Numbers that overflow an u64 are treated as strings (e.g. "1.2.3-9876543210987654321098765432109876543210" parses without error)
///
/// This diagram shows lenient parsing grammar
///
/// ![have a look at doc/railroad.svg](https://knutwalker.s3.eu-central-1.amazonaws.com/lenient-semver/doc/railroad.svg)
///
/// This method can parse anything that implements [`VersionBuilder`].
///
/// ## Examples
///
/// ```rust
/// use lenient_semver::Version;
///
/// let version = lenient_semver::parse_into::<Version>("1.2.3");
/// assert_eq!(version, Ok(Version::new(1, 2, 3)));
///
/// // examples of a version that would not be accepted by semver_parser
/// assert_eq!(
///     lenient_semver::parse_into::<Version>("1.2.M1").unwrap(),
///     Version::parse("1.2.0-M1").unwrap()
/// );
///
/// assert_eq!(
///     lenient_semver::parse_into::<Version>("1").unwrap(),
///     Version::parse("1.0.0").unwrap()
/// );
///
/// assert_eq!(
///     lenient_semver::parse_into::<Version>("1.2.3.Final").unwrap(),
///     Version::parse("1.2.3+Final").unwrap()
/// );
///
/// assert_eq!(
///     lenient_semver::parse_into::<Version>("1.2.3.4.5").unwrap(),
///     Version::parse("1.2.3.4.5").unwrap()
/// );
///
/// assert_eq!(
///     lenient_semver::parse_into::<Version>("v1.2.3").unwrap(),
///     Version::parse("1.2.3").unwrap()
/// );
///
/// assert_eq!(
///    lenient_semver::parse_into::<Version>("1.2.9876543210987654321098765432109876543210").unwrap(),
///    Version::parse("1.2.0-9876543210987654321098765432109876543210").unwrap()
/// );
/// ```
pub fn parse_into<'input, V>(input: &'input str) -> Result<V::Out, parser::Error<'input>>
where
    V: VersionBuilder<'input>,
{
    parser::parse::<V>(input)
}

#[cfg(test)]
mod tests;