Enable warnings as errors (#517)

Author: gjcairo

.github/workflows/main.yml

@@ -11,10 +11,10 @@ jobs:
     name: Unit tests
     uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
     with:
-      linux_5_10_arguments_override: "--explicit-target-dependency-import-check error"
-      linux_6_0_arguments_override: "--explicit-target-dependency-import-check error"
-      linux_6_1_arguments_override: "--explicit-target-dependency-import-check error"
-      linux_nightly_next_arguments_override: "--explicit-target-dependency-import-check error"
+      linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+      linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+      linux_6_1_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+      linux_nightly_next_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_nightly_main_arguments_override: "--explicit-target-dependency-import-check error"
 
   cxx-interop:

.github/workflows/pull_request.yml

@@ -15,10 +15,10 @@ jobs:
     name: Unit tests
     uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
     with:
-      linux_5_10_arguments_override: "--explicit-target-dependency-import-check error"
-      linux_6_0_arguments_override: "--explicit-target-dependency-import-check error"
-      linux_6_1_arguments_override: "--explicit-target-dependency-import-check error"
-      linux_nightly_next_arguments_override: "--explicit-target-dependency-import-check error"
+      linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+      linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+      linux_6_1_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+      linux_nightly_next_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
       linux_nightly_main_arguments_override: "--explicit-target-dependency-import-check error"
 
   cxx-interop:

Sources/NIOHTTP2/HTTP2FrameParser.swift

@@ -1155,7 +1155,7 @@ struct HTTP2FrameDecoder {
             }
         } catch is IgnoredFrame {
             return nil
-        } catch _ as NIOHPACKError {
+        } catch is any NIOHPACKError {
             // convert into a connection error of type COMPRESSION_ERROR
             throw InternalError.codecError(code: .compressionError)
         }

Sources/NIOHTTP2/StreamStateMachine.swift

@@ -526,7 +526,7 @@ extension HTTP2StreamStateMachine {
                     effect: nil
                 )
             }
-        } catch let error where error is InvalidContentLengthError {
+        } catch let error where error is (any InvalidContentLengthError) {
             return .init(
                 result: .streamError(streamID: self.streamID, underlyingError: error, type: .protocolError),
                 effect: nil
@@ -755,7 +755,7 @@ extension HTTP2StreamStateMachine {
                     effect: nil
                 )
             }
-        } catch let error where error is InvalidContentLengthError {
+        } catch let error where error is (any InvalidContentLengthError) {
             return .init(
                 result: .streamError(streamID: self.streamID, underlyingError: error, type: .protocolError),
                 effect: nil