Add support for comparing commits.

README.md

@@ -108,6 +108,7 @@ GitHub.jl implements a bunch of methods that make REST requests to GitHub's API.
 | `stats(repo, stat[, attempts = 3])`                      | `HTTP.Response`                | [get information on `stat` (e.g. "contributors", "code_frequency", "commit_activity", etc.)](https://developer.github.com/v3/repos/statistics/) |
 | `commit(repo, sha)`                                      | `Commit`                       | [get the commit specified by `sha`](https://developer.github.com/v3/repos/commits/#get-a-single-commit)                                         |
 | `commits(repo)`                                          | `Tuple{Vector{Commit}, Dict}`  | [get `repo`'s commits](https://developer.github.com/v3/repos/commits/#list-commits-on-a-repository)                                             |
+| `compare(repo, base, head)`                              | `Comparison`                   | [compare `repo`'s commits](https://docs.github.com/en/rest/commits/commits#compare-two-commits)                                                 |
 | `branch(repo, branch)`                                   | `Branch`                       | [get the branch specified by `branch`](https://developer.github.com/v3/repos/#get-branch)                                                       |
 | `branches(repo)`                                         | `Tuple{Vector{Branch}, Dict}`  | [get `repo`'s branches](https://developer.github.com/v3/repos/#list-branches)                                                                   |
 | `file(repo, path)`                                       | `Content`                      | [get the file specified by `path`](https://developer.github.com/v3/repos/contents/#get-contents)                                                |

src/GitHub.jl

@@ -110,6 +110,7 @@ include("repositories/statuses.jl")
 include("repositories/webhooks.jl")
 include("repositories/deploykeys.jl")
 include("repositories/secrets.jl")
+include("repositories/compare.jl")
 
 # export -------
 
@@ -143,6 +144,10 @@ export # commits.jl
        commit,
        commits
 
+export # compare.jl
+       Comparison,
+       compare
+
 export # branches.jl
        Branch,
        branch,

src/repositories/compare.jl

@@ -0,0 +1,28 @@
+###################
+# Comparison Type #
+###################
+
+@ghdef mutable struct Comparison
+    url::Union{URIs.URI, Nothing}
+    html_url::Union{URIs.URI, Nothing}
+    permalink_url::Union{URIs.URI, Nothing}
+    diff_url::Union{URIs.URI, Nothing}
+    patch_url::Union{URIs.URI, Nothing}
+    base_commit::Union{Commit, Nothing}
+    merge_base_commit::Union{Commit, Nothing}
+    status::Union{String, Nothing}
+    ahead_by::Union{Int, Nothing}
+    behind_by::Union{Int, Nothing}
+    total_commits::Union{Int, Nothing}
+    commits::Union{Vector{Commit}, Nothing}
+    files::Union{Vector{Content}, Nothing}
+end
+
+###############
+# API Methods #
+###############
+
+@api_default function compare(api::GitHubAPI, repo, base, head; options...)
+    result = gh_get_json(api, "/repos/$(name(repo))/compare/$(name(base))...$(name(head))"; options...)
+    return Comparison(result)
+end

test/read_only_api_tests.jl

@@ -78,6 +78,13 @@ end
     @test name(commit(ghjl, testcommit; auth = auth)) == name(testcommit)
     @test hasghobj(testcommit, first(commits(ghjl; auth = auth)))
 
+    # test GitHub.compare
+    @test compare(ghjl, "master", "master~"; auth = auth).behind_by == 1
+    let comparison = compare(ghjl, "master~", "master"; auth = auth)
+        @test comparison.ahead_by == 1
+        @test length(comparison.commits) == 1
+    end
+
     # test GitHub.file, GitHub.directory, GitHub.readme, GitHub.permalink
     readme_file = file(ghjl, "README.md"; auth = auth)
     src_dir = first(directory(ghjl, "src"; auth = auth))