Revert "Fix accidentally-introduced warnings and regression in test behavior in PIFLoadingTests"

The original code was correct and these changes overlooked some context as to why the original code was the way it was (e.g., the warnings are due to a compiler bug, #require will already emit an issue).

But we can work around most of the warnings by casting to an optional, which is low-profile and allows us to retain the same approach to these checks, so that has been added where possible.

This reverts commit a6a6bb7.

Author: mhrawdon

Tests/SWBCoreTests/PIFLoadingTests.swift

@@ -683,24 +683,19 @@ private final class ProjectModelItemClass: ProjectModelItem {
         #expect(fileGroup.children.count == 2)
 
         // Examine its children
-        if let fileRef = fileGroup.children.first as? FileReference {
+        if let fileRef = try? #require(fileGroup.children.first as? FileReference?) {
             #expect(fileRef.guid == "first-fileReference-guid")
             #expect(fileRef.sourceTree == SourceTree.groupRelative)
             #expect(fileRef.path.stringRep == "ClassOne.m")
             #expect(fileRef.fileTypeIdentifier == "sourcecode.c.objc")
             #expect(fileRef.regionVariantName == nil)
-        } else {
-            Issue.record("Missing file reference in group")
         }
-
-        if let fileRef = fileGroup.children[1] as? FileReference {
+        if let fileRef = try? #require(fileGroup.children[1] as? FileReference?) {
             #expect(fileRef.guid == "second-fileReference-guid")
             #expect(fileRef.sourceTree == SourceTree.groupRelative)
             #expect(fileRef.path.stringRep == "ClassOne.h")
             #expect(fileRef.fileTypeIdentifier == "sourcecode.c.h")
             #expect(fileRef.regionVariantName == nil)
-        } else {
-            Issue.record("Missing file reference in group")
         }
     }
 
@@ -745,24 +740,19 @@ private final class ProjectModelItemClass: ProjectModelItem {
         #expect(versionGroup.children.count == 2)
 
         // Examine its children
-        if let fileRef = versionGroup.children[0] as? FileReference {
+        if let fileRef = try? #require(versionGroup.children[0] as? FileReference?) {
             #expect(fileRef.guid == "first-versionedFile-guid")
             #expect(fileRef.sourceTree == SourceTree.groupRelative)
             #expect(fileRef.path.stringRep == "CoreData-1.xcdatamodel")
             #expect(fileRef.fileTypeIdentifier == "wrapper.xcdatamodel")
             #expect(fileRef.regionVariantName == nil)
-        } else {
-            Issue.record("Missing file reference in group")
         }
-
-        if let fileRef = versionGroup.children[1] as? FileReference {
+        if let fileRef = try? #require(versionGroup.children[1] as? FileReference?) {
             #expect(fileRef.guid == "second-versionedFile-guid")
             #expect(fileRef.sourceTree == SourceTree.groupRelative)
             #expect(fileRef.path.stringRep == "CoreData-2.xcdatamodel")
             #expect(fileRef.fileTypeIdentifier == "wrapper.xcdatamodel")
             #expect(fileRef.regionVariantName == nil)
-        } else {
-            Issue.record("Missing file reference in group")
         }
     }
 
@@ -831,34 +821,26 @@ private final class ProjectModelItemClass: ProjectModelItem {
         #expect(variantGroup.name == "Thingy.xib")
 
         // Examine its children, the xib and its localized strings files
-        if let fileRef = variantGroup.children[0] as? FileReference {
+        if let fileRef = try? #require(variantGroup.children[0] as? FileReference?) {
             #expect(fileRef.guid == "xib-fileReference-guid")
             #expect(fileRef.sourceTree == SourceTree.groupRelative)
             #expect(fileRef.path.stringRep == "Thingy.xib")
             #expect(fileRef.fileTypeIdentifier == "file.xib")
             #expect(fileRef.regionVariantName == nil)
-        } else {
-            Issue.record("Missing file reference in group")
         }
-
-        if let fileRef = variantGroup.children[1] as? FileReference {
+        if let fileRef = try? #require(variantGroup.children[1] as? FileReference?) {
             #expect(fileRef.guid == "fr-strings-fileReference-guid")
             #expect(fileRef.sourceTree == SourceTree.groupRelative)
             #expect(fileRef.path.stringRep == "Thingy.strings")
             #expect(fileRef.fileTypeIdentifier == "text.plist.strings")
             #expect(fileRef.regionVariantName == "fr")
-        } else {
-            Issue.record("Missing file reference in group")
         }
-
-        if let fileRef = variantGroup.children[2] as? FileReference {
+        if let fileRef = try? #require(variantGroup.children[2] as? FileReference?) {
             #expect(fileRef.guid == "de-strings-fileReference-guid")
             #expect(fileRef.sourceTree == SourceTree.groupRelative)
             #expect(fileRef.path.stringRep == "Thingy.strings")
             #expect(fileRef.fileTypeIdentifier == "text.plist.strings")
             #expect(fileRef.regionVariantName == "de")
-        } else {
-            Issue.record("Missing file reference in group")
         }
     }
 
@@ -959,14 +941,10 @@ private final class ProjectModelItemClass: ProjectModelItem {
             ]
 
             // Convert the test data into a property list, then read the build phase from it.
-            #expect(throws: Never.self, performing: {
-                if let buildPhase = try BuildPhase.parsePIFDictAsBuildPhase(buildPhasePIF, pifLoader: pifLoader) as? SourcesBuildPhase {
-                    // Examine the build phase.
-                    #expect(buildPhase.buildFiles.count == 1)
-                } else {
-                    Issue.record("Unexpected build phase type")
-                }
-            })
+            if let buildPhase = try? #require(BuildPhase.parsePIFDictAsBuildPhase(buildPhasePIF, pifLoader: pifLoader) as? SourcesBuildPhase?) {
+                // Examine the build phase.
+                #expect(buildPhase.buildFiles.count == 1)
+            }
         }
 
         // A headers build phase
@@ -984,14 +962,10 @@ private final class ProjectModelItemClass: ProjectModelItem {
             ]
 
             // Convert the test data into a property list, then read the build phase from it.
-            #expect(throws: Never.self, performing: {
-                if let buildPhase = try BuildPhase.parsePIFDictAsBuildPhase(buildPhasePIF, pifLoader: pifLoader) as? HeadersBuildPhase {
-                    // Examine the build phase.
-                    #expect(buildPhase.buildFiles.count == 1)
-                } else {
-                    Issue.record("Unexpected build phase type")
-                }
-            })
+            if let buildPhase = try? #require(BuildPhase.parsePIFDictAsBuildPhase(buildPhasePIF, pifLoader: pifLoader) as? HeadersBuildPhase?) {
+                // Examine the build phase.
+                #expect(buildPhase.buildFiles.count == 1)
+            }
         }
 
         // A resources build phase
@@ -1009,14 +983,10 @@ private final class ProjectModelItemClass: ProjectModelItem {
             ]
 
             // Convert the test data into a property list, then read the build phase from it.
-            #expect(throws: Never.self, performing: {
-                if let buildPhase = try BuildPhase.parsePIFDictAsBuildPhase(buildPhasePIF, pifLoader: pifLoader) as? ResourcesBuildPhase {
-                    // Examine the build phase.
-                    #expect(buildPhase.buildFiles.count == 1)
-                } else {
-                    Issue.record("Unexpected build phase type")
-                }
-            })
+            if let buildPhase = try? #require(BuildPhase.parsePIFDictAsBuildPhase(buildPhasePIF, pifLoader: pifLoader) as? ResourcesBuildPhase?) {
+                // Examine the build phase.
+                #expect(buildPhase.buildFiles.count == 1)
+            }
         }
 
         // A copy files build phase
@@ -1037,17 +1007,13 @@ private final class ProjectModelItemClass: ProjectModelItem {
             ]
 
             // Convert the test data into a property list, then read the build phase from it.
-            #expect(throws: Never.self, performing: {
-                if let buildPhase = try BuildPhase.parsePIFDictAsBuildPhase(buildPhasePIF, pifLoader: pifLoader) as? CopyFilesBuildPhase {
-                    // Examine the build phase.
-                    #expect(buildPhase.destinationSubfolder.stringRep == "Resources")
-                    #expect(buildPhase.destinationSubpath.stringRep == "Subpath")
-                    #expect(buildPhase.buildFiles.count == 1)
-                    #expect(buildPhase.runOnlyForDeploymentPostprocessing);
-                } else {
-                    Issue.record("Unexpected build phase type")
-                }
-            })
+            if let buildPhase = try? #require(BuildPhase.parsePIFDictAsBuildPhase(buildPhasePIF, pifLoader: pifLoader) as? CopyFilesBuildPhase?) {
+                // Examine the build phase.
+                #expect(buildPhase.destinationSubfolder.stringRep == "Resources")
+                #expect(buildPhase.destinationSubpath.stringRep == "Subpath")
+                #expect(buildPhase.buildFiles.count == 1)
+                #expect(buildPhase.runOnlyForDeploymentPostprocessing);
+            }
         }
 
         // A shell script build phase
@@ -1070,24 +1036,20 @@ private final class ProjectModelItemClass: ProjectModelItem {
             ]
 
             // Convert the test data into a property list, then read the build phase from it.
-            #expect(throws: Never.self, performing: {
-                if let buildPhase = try BuildPhase.parsePIFDictAsBuildPhase(buildPhasePIF, pifLoader: pifLoader) as? ShellScriptBuildPhase {
-                    // Examine the build phase.
-                    #expect(buildPhase.guid == "some-shellScriptBuildPhase-guid")
-                    #expect(buildPhase.name == "A Shell Script Phase")
-                    #expect(buildPhase.shellPath.stringRep == "/bin/sh")
-                    #expect(buildPhase.scriptContents == "echo \"Nothing to do.\"\nexit 0")
-                    #expect(buildPhase.originalObjectID == "1234512345")
-                    #expect(buildPhase.inputFilePaths.count == 1)
-                    #expect(buildPhase.inputFilePaths.first?.stringRep == "/tmp/foo.in")
-                    #expect(buildPhase.outputFilePaths.count == 1)
-                    #expect(buildPhase.outputFilePaths.first?.stringRep == "/tmp/foo.out")
-                    #expect(buildPhase.emitEnvironment);
-                    #expect(buildPhase.runOnlyForDeploymentPostprocessing);
-                } else {
-                    Issue.record("Unexpected build phase type")
-                }
-            })
+            if let buildPhase = try? #require(BuildPhase.parsePIFDictAsBuildPhase(buildPhasePIF, pifLoader: pifLoader) as? ShellScriptBuildPhase?) {
+                // Examine the build phase.
+                #expect(buildPhase.guid == "some-shellScriptBuildPhase-guid")
+                #expect(buildPhase.name == "A Shell Script Phase")
+                #expect(buildPhase.shellPath.stringRep == "/bin/sh")
+                #expect(buildPhase.scriptContents == "echo \"Nothing to do.\"\nexit 0")
+                #expect(buildPhase.originalObjectID == "1234512345")
+                #expect(buildPhase.inputFilePaths.count == 1)
+                #expect(buildPhase.inputFilePaths.first?.stringRep == "/tmp/foo.in")
+                #expect(buildPhase.outputFilePaths.count == 1)
+                #expect(buildPhase.outputFilePaths.first?.stringRep == "/tmp/foo.out")
+                #expect(buildPhase.emitEnvironment);
+                #expect(buildPhase.runOnlyForDeploymentPostprocessing);
+            }
         }
     }
 
@@ -1391,8 +1353,7 @@ private final class ProjectModelItemClass: ProjectModelItem {
 
             // Because of the way reference resolution of a BuildFile.BuildableItem works, we don't have a context to resolve the build file's references to real references, so all we can do is check that the GUID is what we expect.
             func checkBuildFileRef(of buildPhase: BuildPhaseWithBuildFiles, fileRef: FileReference) throws {
-                guard let buildFileRef = buildPhase.buildFiles.first else {
-                    Issue.record("No build file in build phase")
+                guard let buildFileRef = try? #require(buildPhase.buildFiles.first) else {
                     return
                 }
                 guard case let .reference(buildFileRefGuid) = buildFileRef.buildableItem else {