Add expectations for default member deser (smithy-lang#365)

This adds expectations for the default member deserialization so that
an error will be thrown if the type being deserialized isn't correct.

Author: JordonPhillips

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/integration/DocumentMemberDeserVisitor.java

@@ -124,46 +124,48 @@ public String blobShape(BlobShape shape) {
 
     @Override
     public String booleanShape(BooleanShape shape) {
-        return deserializeUnmodified();
+        context.getWriter().addImport("expectBoolean", "__expectBoolean", "@aws-sdk/smithy-client");
+        return "__expectBoolean(" + dataSource + ")";
     }
 
     @Override
     public String byteShape(ByteShape shape) {
-        return deserializeUnmodified();
+        return expectNumber();
     }
 
     @Override
     public String shortShape(ShortShape shape) {
-        return deserializeUnmodified();
+        return expectNumber();
     }
 
     @Override
     public String integerShape(IntegerShape shape) {
-        return deserializeUnmodified();
+        return expectNumber();
     }
 
     @Override
     public String longShape(LongShape shape) {
-        return deserializeUnmodified();
+        return expectNumber();
     }
 
     @Override
     public String floatShape(FloatShape shape) {
-        return deserializeUnmodified();
+        return expectNumber();
     }
 
     @Override
     public String doubleShape(DoubleShape shape) {
-        return deserializeUnmodified();
+        return expectNumber();
     }
 
-    @Override
-    public String stringShape(StringShape shape) {
-        return HttpProtocolGeneratorUtils.getStringOutputParam(context, shape, deserializeUnmodified());
+    private String expectNumber() {
+        context.getWriter().addImport("expectNumber", "__expectNumber", "@aws-sdk/smithy-client");
+        return "__expectNumber(" + dataSource + ")";
     }
 
-    private String deserializeUnmodified() {
-        return dataSource;
+    @Override
+    public String stringShape(StringShape shape) {
+        return HttpProtocolGeneratorUtils.getStringOutputParam(context, shape, dataSource);
     }
 
     @Override

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/integration/HttpBindingProtocolGenerator.java

@@ -2470,7 +2470,12 @@ private String getStringOutputParam(
             dataSource = "Buffer.from(" + dataSource + ", 'base64').toString('ascii')";
         }
 
-        return HttpProtocolGeneratorUtils.getStringOutputParam(context, target, dataSource);
+        return HttpProtocolGeneratorUtils.getStringOutputParam(
+                context, target, dataSource, !isGuaranteedString(bindingType));
+    }
+
+    private boolean isGuaranteedString(Location bindingType) {
+        return bindingType != Location.PAYLOAD && bindingType != Location.DOCUMENT;
     }
 
     /**

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/integration/HttpProtocolGeneratorUtils.java

@@ -158,9 +158,11 @@ static String getStringInputParam(GenerationContext context, Shape shape, String
      * @param shape The shape that represents the value being received.
      * @param dataSource The in-code location of the data to provide an output of
      *   ({@code output.foo}, {@code entry}, etc.)
+     * @param useExpect Whether or not to wrap the string in expectString. This should
+     *   only be false if the value is guaranteed to be a string already.
      * @return Returns a value or expression of the output string.
      */
-    static String getStringOutputParam(GenerationContext context, Shape shape, String dataSource) {
+    static String getStringOutputParam(GenerationContext context, Shape shape, String dataSource, boolean useExpect) {
         // Handle media type generation, defaulting to a standard String.
         Optional<MediaTypeTrait> mediaTypeTrait = shape.getTrait(MediaTypeTrait.class);
         if (mediaTypeTrait.isPresent()) {
@@ -173,7 +175,28 @@ static String getStringOutputParam(GenerationContext context, Shape shape, Strin
                 LOGGER.warning(() -> "Found unsupported mediatype " + mediaType + " on String shape: " + shape);
             }
         }
-        return dataSource;
+
+        if (!useExpect) {
+            return dataSource;
+        }
+        context.getWriter().addImport("expectString", "__expectString", "@aws-sdk/smithy-client");
+        return "__expectString(" + dataSource + ")";
+    }
+
+    /**
+     * Given a String output, determine its media type and generate an output value
+     * provider for it.
+     *
+     * <p>This currently only supports using the LazyJsonString for {@code "application/json"}.
+     *
+     * @param context The generation context.
+     * @param shape The shape that represents the value being received.
+     * @param dataSource The in-code location of the data to provide an output of
+     *   ({@code output.foo}, {@code entry}, etc.)
+     * @return Returns a value or expression of the output string.
+     */
+    static String getStringOutputParam(GenerationContext context, Shape shape, String dataSource) {
+        return getStringOutputParam(context, shape, dataSource, true);
     }
 
     /**

smithy-typescript-codegen/src/test/java/software/amazon/smithy/typescript/codegen/integration/DocumentMemberDeserVisitorTest.java

@@ -68,14 +68,14 @@ public static Collection<Object[]> validMemberTargetTypes() {
                 + "(" + DATA_SOURCE + ", context)";
 
         return ListUtils.of(new Object[][]{
-                {BooleanShape.builder().id(id).build(), DATA_SOURCE},
-                {ByteShape.builder().id(id).build(), DATA_SOURCE},
-                {DoubleShape.builder().id(id).build(), DATA_SOURCE},
-                {FloatShape.builder().id(id).build(), DATA_SOURCE},
-                {IntegerShape.builder().id(id).build(), DATA_SOURCE},
-                {LongShape.builder().id(id).build(), DATA_SOURCE},
-                {ShortShape.builder().id(id).build(), DATA_SOURCE},
-                {StringShape.builder().id(id).build(), DATA_SOURCE},
+                {BooleanShape.builder().id(id).build(), "__expectBoolean(" + DATA_SOURCE + ")"},
+                {ByteShape.builder().id(id).build(), "__expectNumber(" + DATA_SOURCE + ")"},
+                {DoubleShape.builder().id(id).build(), "__expectNumber(" + DATA_SOURCE + ")"},
+                {FloatShape.builder().id(id).build(), "__expectNumber(" + DATA_SOURCE + ")"},
+                {IntegerShape.builder().id(id).build(), "__expectNumber(" + DATA_SOURCE + ")"},
+                {LongShape.builder().id(id).build(), "__expectNumber(" + DATA_SOURCE + ")"},
+                {ShortShape.builder().id(id).build(), "__expectNumber(" + DATA_SOURCE + ")"},
+                {StringShape.builder().id(id).build(), "__expectString(" + DATA_SOURCE + ")"},
                 {
                     StringShape.builder().id(id).addTrait(new MediaTypeTrait("foo+json")).build(),
                     "new __LazyJsonString(" + DATA_SOURCE + ")"