Pypi: Expand test coverage

Among other things, the previous commit added a `provided_content`
paramter to `Pypi::find_versions`, so this takes advantage of that to
expand `Pypi` test coverage to 100%.

Library/Homebrew/test/livecheck/strategy/pypi_spec.rb

@@ -8,12 +8,42 @@ RSpec.describe Homebrew::Livecheck::Strategy::Pypi do
   let(:pypi_url) { "https://files.pythonhosted.org/packages/ab/cd/efg/example-package-1.2.3.tar.gz" }
   let(:non_pypi_url) { "https://brew.sh/test" }
 
+  let(:regex) { /^v?(\d+(?:\.\d+)+)$/i }
+
   let(:generated) do
     {
       url: "https://pypi.org/pypi/example-package/json",
     }
   end
 
+  # This is a limited subset of a PyPI JSON API response object, for the sake
+  # of testing.
+  let(:content) do
+    <<~JSON
+      {
+        "info": {
+          "version": "1.2.3"
+        }
+      }
+    JSON
+  end
+
+  let(:matches) { ["1.2.3"] }
+
+  let(:find_versions_return_hash) do
+    {
+      matches: {
+        "1.2.3" => Version.new("1.2.3"),
+      },
+      regex:   nil,
+      url:     generated[:url],
+    }
+  end
+
+  let(:find_versions_cached_return_hash) do
+    find_versions_return_hash.merge({ cached: true })
+  end
+
   describe "::match?" do
     it "returns true for a PyPI URL" do
       expect(pypi.match?(pypi_url)).to be true
@@ -33,4 +63,59 @@ RSpec.describe Homebrew::Livecheck::Strategy::Pypi do
       expect(pypi.generate_input_values(non_pypi_url)).to eq({})
     end
   end
+
+  describe "::find_versions" do
+    let(:match_data) do
+      cached = {
+        matches: matches.to_h { |v| [v, Version.new(v)] },
+        regex:   nil,
+        url:     generated[:url],
+        cached:  true,
+      }
+
+      {
+        cached:,
+        cached_default: cached.merge({ matches: {} }),
+      }
+    end
+
+    it "finds versions in provided content" do
+      expect(pypi.find_versions(url: pypi_url, provided_content: content))
+        .to eq(match_data[:cached])
+    end
+
+    it "finds versions in provided content using a block" do
+      # NOTE: We only use a regex here to make sure it can be passed into the
+      # block, if necessary.
+      expect(pypi.find_versions(url: pypi_url, regex:, provided_content: content) do |json, regex|
+        match = json.dig("info", "version")&.match(regex)
+        next if match.blank?
+
+        match[1]
+      end).to eq(match_data[:cached].merge({ regex: }))
+
+      expect(pypi.find_versions(url: pypi_url, provided_content: content) do |json|
+        json.dig("info", "version").presence
+      end).to eq(match_data[:cached])
+    end
+
+    it "returns default match_data when block doesn't return version information" do
+      expect(pypi.find_versions(url: pypi_url, provided_content: '{"info":{"version":""}}'))
+        .to eq(match_data[:cached_default])
+      expect(pypi.find_versions(url: pypi_url, provided_content: '{"other":true}'))
+        .to eq(match_data[:cached_default])
+    end
+
+    it "returns default match_data when url is blank" do
+      expect(pypi.find_versions(url: "") { "1.2.3" })
+        .to eq({ matches: {}, regex: nil, url: "" })
+    end
+
+    it "returns default match_data when content is blank" do
+      expect(pypi.find_versions(url: pypi_url, provided_content: "{}") { "1.2.3" })
+        .to eq(match_data[:cached_default])
+      expect(pypi.find_versions(url: pypi_url, provided_content: "") { "1.2.3" })
+        .to eq(match_data[:cached_default])
+    end
+  end
 end