Add spell checking support.

src/main/kotlin/software/amazon/smithy/intellij/SmithySpellcheckingStrategy.kt

@@ -0,0 +1,56 @@
+package software.amazon.smithy.intellij
+
+import com.intellij.openapi.util.TextRange
+import com.intellij.psi.PsiComment
+import com.intellij.psi.PsiDocCommentBase
+import com.intellij.psi.PsiElement
+import com.intellij.psi.PsiNameIdentifierOwner
+import com.intellij.spellchecker.inspections.CommentSplitter
+import com.intellij.spellchecker.inspections.PlainTextSplitter
+import com.intellij.spellchecker.inspections.Splitter
+import com.intellij.spellchecker.tokenizer.PsiIdentifierOwnerTokenizer
+import com.intellij.spellchecker.tokenizer.SpellcheckingStrategy
+import com.intellij.spellchecker.tokenizer.TokenConsumer
+import com.intellij.spellchecker.tokenizer.Tokenizer
+import software.amazon.smithy.intellij.psi.SmithyString
+import software.amazon.smithy.intellij.psi.SmithyTextBlock
+
+/**
+ * A [SpellcheckingStrategy] for [Smithy](https://awslabs.github.io/smithy) IDL model files.
+ *
+ * @author Ian Caffey
+ * @since 1.0
+ */
+class SmithySpellcheckingStrategy : SpellcheckingStrategy() {
+    override fun getTokenizer(element: PsiElement): Tokenizer<out PsiElement> = when (element) {
+        is PsiComment -> CommentTokenizer
+        is PsiNameIdentifierOwner -> PsiIdentifierOwnerTokenizer()
+        is SmithyString -> StringTokenizer
+        is SmithyTextBlock -> TextBlockTokenizer
+        else -> EMPTY_TOKENIZER
+    }
+}
+
+abstract class SimpleTokenizer<T : PsiElement> : Tokenizer<T>() {
+    abstract val splitter: Splitter
+    abstract fun textRange(t: T): TextRange
+    override fun tokenize(t: T, consumer: TokenConsumer) {
+        consumer.consumeToken(t, t.text, false, 0, textRange(t), splitter)
+    }
+}
+
+object CommentTokenizer : SimpleTokenizer<PsiComment>() {
+    override val splitter = CommentSplitter.getInstance()
+    override fun textRange(comment: PsiComment) =
+        TextRange.create(if (comment is PsiDocCommentBase) 3 else 2, comment.textLength)
+}
+
+object StringTokenizer : SimpleTokenizer<SmithyString>() {
+    override val splitter = PlainTextSplitter.getInstance()
+    override fun textRange(string: SmithyString) = TextRange.create(1, string.textLength - 1)
+}
+
+object TextBlockTokenizer : SimpleTokenizer<SmithyTextBlock>() {
+    override val splitter = PlainTextSplitter.getInstance()
+    override fun textRange(text: SmithyTextBlock) = TextRange.create(3, text.textLength - 3)
+}

src/main/resources/META-INF/plugin.xml

@@ -93,5 +93,7 @@
         <iconProvider implementation="software.amazon.smithy.intellij.SmithyIconProvider"/>
         <liveTemplateContext implementation="software.amazon.smithy.intellij.SmithyContextType"/>
         <navbar implementation="software.amazon.smithy.intellij.SmithyNavBar"/>
+        <spellchecker.support language="Smithy"
+                              implementationClass="software.amazon.smithy.intellij.SmithySpellcheckingStrategy"/>
     </extensions>
-</idea-plugin>
+</idea-plugin>