utils/pypi: make package name comparison case-insensitive

Library/Homebrew/test/utils/pypi_spec.rb

@@ -22,6 +22,7 @@ describe PyPI do
     let(:package_with_different_version) { described_class.new("snakemake==5.29.0") }
     let(:package_with_extra) { described_class.new("snakemake[foo]") }
     let(:package_with_extra_and_version) { described_class.new("snakemake[foo]==5.28.0") }
+    let(:package_with_different_capitalization) { described_class.new("SNAKEMAKE") }
     let(:package_from_url) { described_class.new(package_url, is_url: true) }
     let(:other_package) { described_class.new("virtualenv==20.2.0") }
 
@@ -146,6 +147,10 @@ describe PyPI do
       it "returns true for the same package with different versions" do
         expect(package_with_version.same_package?(package_with_different_version)).to eq true
       end
+
+      it "returns true for the same package with different capitalization" do
+        expect(package.same_package?(package_with_different_capitalization)).to eq true
+      end
     end
 
     describe "<=>" do

Library/Homebrew/utils/pypi.rb

@@ -91,7 +91,7 @@ module PyPI
 
     sig { params(other: Package).returns(T::Boolean) }
     def same_package?(other)
-      @name.tr("_", "-") == other.name.tr("_", "-")
+      @name.downcase.tr("_", "-") == other.name.downcase.tr("_", "-")
     end
 
     # Compare only names so we can use .include? on a Package array
@@ -231,7 +231,7 @@ module PyPI
     end
 
     # Remove extra packages that may be included in pipgrip output
-    exclude_list = %W[#{main_package.name.downcase} argparse pip setuptools wheel wsgiref].map { |p| Package.new p }
+    exclude_list = %W[#{main_package.name} argparse pip setuptools wheel wsgiref].map { |p| Package.new p }
     found_packages.delete_if { |package| exclude_list.include? package }
 
     new_resource_blocks = ""