make references into links to make changelogs more navigable (#1059)

use crate::lint::LintError;

use crate::{repo_root, Check, Lint};

use anyhow::{bail, Context, Result};

use serde::Deserialize;

use serde::{de, Deserialize, Deserializer};

use std::fmt::Write;

use std::path::{Path, PathBuf};

use std::process::Command;

use std::str::FromStr;

const EXAMPLE_ENTRY: &str = r#"

# Example changelog entries

    meta: Meta,

    author: String,

    #[serde(default)]

    references: Vec<String>,

    references: Vec<Reference>,

}

struct Reference {

    repo: String,

    number: usize,

}

impl Reference {

    fn to_md_link(&self) -> String {

        format!(

            "[{repo}#{number}](https://github.com/awslabs/{repo}/issues/{number})",

            repo = self.repo,

            number = self.number

        )

    }

}

impl<'de> Deserialize<'de> for Reference {

    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

    where

        D: Deserializer<'de>,

    {

        let s = String::deserialize(deserializer)?;

        FromStr::from_str(&s).map_err(de::Error::custom)

    }

}

impl FromStr for Reference {

    type Err = anyhow::Error;

    fn from_str(reference: &str) -> std::result::Result<Self, Self::Err> {

        match reference.split_once('#') {

            None => bail!(

                "Reference must of the form `repo#number` but found {}",

                reference

            ),

            Some((repo, number)) => {

                let number = number.parse::<usize>()?;

                if !matches!(repo, "smithy-rs" | "aws-sdk-rust") {

                    bail!("unexpected repo: {}", repo);

                }

                Ok(Reference {

                    number,

                    repo: repo.to_string(),

                })

            }

        }

    }

}

impl ChangelogEntry {

        if !meta.is_empty() {

            meta.push(' ');

        }

        let mut references = self.references.clone();

        let mut references = self

            .references

            .iter()

            .map(Reference::to_md_link)

            .collect::<Vec<_>>();

        if !maintainers().contains(&self.author.to_ascii_lowercase().as_str()) {

            references.push(format!("@{}", self.author.to_ascii_lowercase()));

        };

                        .author

                        .eq_ignore_ascii_case(contributor_handle.as_str())

                })

                .flat_map(|entry| entry.references.iter().map(|it| it.as_str()))

                .flat_map(|entry| entry.references.iter().map(|it| it.to_md_link()))

                .collect::<Vec<_>>();

            contribution_references.sort();

            contribution_references.dedup();

        bail!("Changelog entry must refer to at least one pull request or issue");

    }

    for reference in &entry.references {

        match reference.split_once('#') {

            None => bail!(

                "Reference must of the form `repo#number` but found {}",

                reference

            ),

            Some(("aws-sdk-rust" | "smithy-rs", number)) if number.parse::<u32>().is_ok() => {}

            _other => bail!(

                "unexpected reference format: {} (expected aws-sdk-rust/smithy-rs#number)",

                reference

            ),

        }

    }

    Ok(())

}

v0.3.0 (January 4th, 2022)

==========================

**Breaking Changes:**

- ⚠ (smithy-rs#445) I made a major change to update the code generator

- ⚠ ([smithy-rs#445](https://github.com/awslabs/smithy-rs/issues/445)) I made a major change to update the code generator

**New this release:**

- 🎉 (smithy-rs#446, @external-contrib) I made a change to update the code generator

- 🎉 (smithy-rs#446, @external-contrib) I made a change to update the code generator

- 🎉 ([smithy-rs#446](https://github.com/awslabs/smithy-rs/issues/446), @external-contrib) I made a change to update the code generator

- 🎉 ([smithy-rs#446](https://github.com/awslabs/smithy-rs/issues/446), @external-contrib) I made a change to update the code generator

    **Update guide:**

    blah blah

**Contributors**

Thank you for your contributions! ❤

- @another-contrib

- @external-contrib (smithy-rs#446)

- @external-contrib ([smithy-rs#446](https://github.com/awslabs/smithy-rs/issues/446))

"#

        .trim_start();

        assert_eq!(expected, rendered);