Refactoring and adding aws_sdk_unstable to RUSTFLAG on one of the kotlin test

codegen-core/src/main/kotlin/software/amazon/smithy/rust/codegen/core/testutil/Rust.kt

@@ -42,6 +42,43 @@ import java.nio.file.Files.createTempDirectory
 import java.nio.file.Path
 import kotlin.io.path.absolutePathString
 
+// cargo commands and env values
+object Commands {
+    private const val cfgUnstable = "--cfg aws_sdk_unstable"
+    fun func(s: String, add: String, flag: Boolean): String {
+        if (flag) {
+            return s + " " + add
+        } else {
+            return s
+        }
+    }
+
+    fun cargoEnvDWarnings(enableUnstable: Boolean): Map<String, String> {
+        return mapOf(
+            "RUSTFLAGS" to func("-A dead_code", cfgUnstable, enableUnstable),
+        )
+    }
+
+    fun cargoEnvDDeadCode(enableUnstable: Boolean): Map<String, String> {
+        return mapOf(
+            "RUSTFLAGS" to func("-A dead_code", cfgUnstable, enableUnstable),
+        )
+    }
+
+    private const val allFeature = "--all-features"
+
+    fun cargoTest(enableUnstable: Boolean): String {
+        return func("cargo test", allFeature, enableUnstable)
+    }
+
+    fun cargoCheck(enableUnstable: Boolean): String {
+        return func("cargo check", allFeature, enableUnstable)
+    }
+
+    const val CargoFmt = "cargo fmt"
+    const val CargoClippy = "cargo clippy"
+}
+
 val TestModuleDocProvider = object : ModuleDocProvider {
     override fun docsWriter(module: RustModule.LeafModule): Writable = writable {
         docs("Some test documentation\n\nSome more details...")
@@ -316,6 +353,7 @@ fun FileManifest.printGeneratedFiles() {
 fun TestWriterDelegator.compileAndTest(
     runClippy: Boolean = false,
     expectFailure: Boolean = false,
+    enableUnstableFlag: Boolean = false,
 ): String {
     val stubModel = """
         namespace fake
@@ -332,14 +370,15 @@ fun TestWriterDelegator.compileAndTest(
     println("Generated files:")
     printGeneratedFiles()
     try {
-        "cargo fmt".runCommand(baseDir)
+        Commands.CargoFmt.runCommand(baseDir)
     } catch (e: Exception) {
         // cargo fmt errors are useless, ignore
     }
-    val env = mapOf("RUSTFLAGS" to "-A dead_code")
-    val testOutput = "cargo test".runCommand(baseDir, env)
+
+    val env = Commands.cargoEnvDDeadCode(enableUnstableFlag)
+    val testOutput = Commands.cargoTest(enableUnstableFlag).runCommand(baseDir, env)
     if (runClippy) {
-        "cargo clippy".runCommand(baseDir, env)
+        Commands.CargoClippy.runCommand(baseDir, env)
     }
     return testOutput
 }
@@ -366,6 +405,7 @@ fun RustWriter.compileAndTest(
     main: String = "",
     clippy: Boolean = false,
     expectFailure: Boolean = false,
+    enableUnstable: Boolean = false,
 ): String {
     val deps = this.dependencies.map { RustDependency.fromSymbolDependency(it) }.filterIsInstance<CargoDependency>()
     val module = if (this.namespace.contains("::")) {
@@ -379,9 +419,9 @@ fun RustWriter.compileAndTest(
     val testModule = tempDir.resolve("src/$module.rs")
     try {
         val testOutput = if ((mainRs.readText() + testModule.readText()).contains("#[test]")) {
-            "cargo test".runCommand(tempDir.toPath())
+            Commands.cargoTest(enableUnstable).runCommand(tempDir.toPath())
         } else {
-            "cargo check".runCommand(tempDir.toPath())
+            Commands.cargoCheck(enableUnstable).runCommand(tempDir.toPath())
         }
         if (expectFailure) {
             println("Test sources for debugging: file://${testModule.absolutePath}")
@@ -488,4 +528,4 @@ fun TestWriterDelegator.unitTest(test: Writable): TestWriterDelegator {
     return this
 }
 
-fun String.runWithWarnings(crate: Path) = this.runCommand(crate, mapOf("RUSTFLAGS" to "-D warnings"))
+fun String.runWithWarnings(crate: Path, enableUnstableFlag: Boolean = true) = this.runCommand(crate, Commands.cargoEnvDWarnings(enableUnstableFlag))