Replace DocumentParser impl with a real parser

build.gradle

@@ -141,6 +141,9 @@ publishing {
     }
 }
 
+checkstyle {
+    toolVersion = "10.12.4"
+}
 
 dependencies {
     implementation "org.eclipse.lsp4j:org.eclipse.lsp4j:0.23.1"
@@ -153,6 +156,8 @@ dependencies {
     testImplementation "org.hamcrest:hamcrest:2.2"
 
     testRuntimeOnly "org.junit.platform:junit-platform-launcher"
+
+    checkstyle "com.puppycrawl.tools:checkstyle:${checkstyle.toolVersion}"
 }
 
 tasks.withType(Javadoc).all {

src/main/java/software/amazon/smithy/lsp/codeactions/DefineVersionCodeAction.java

@@ -15,14 +15,12 @@
 
 package software.amazon.smithy.lsp.codeactions;
 
-import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import org.eclipse.lsp4j.CodeAction;
-import org.eclipse.lsp4j.Position;
-import org.eclipse.lsp4j.Range;
 import org.eclipse.lsp4j.TextEdit;
 import org.eclipse.lsp4j.WorkspaceEdit;
+import software.amazon.smithy.lsp.protocol.LspAdapter;
 
 public final class DefineVersionCodeAction {
     private static final int DEFAULT_VERSION = 1;
@@ -42,10 +40,9 @@ public static CodeAction build(String fileUri) {
         codeAction.setKind(SmithyCodeActions.SMITHY_DEFINE_VERSION);
         WorkspaceEdit wEdit = new WorkspaceEdit();
         TextEdit edit = new TextEdit(
-            new Range(new Position(0, 0), new Position(0, 0)),
-            "$version: \"" + DEFAULT_VERSION + "\"\n\n"
-        );
-        Map<String, List<TextEdit>> changes = Collections.singletonMap(fileUri, Collections.singletonList(edit));
+                LspAdapter.origin(),
+                String.format("$version: \"%s\"%n%n", DEFAULT_VERSION));
+        Map<String, List<TextEdit>> changes = Map.of(fileUri, List.of(edit));
         wEdit.setChanges(changes);
         codeAction.setEdit(wEdit);
         return codeAction;

src/main/java/software/amazon/smithy/lsp/codeactions/SmithyCodeActions.java

@@ -62,11 +62,8 @@ public static List<CodeAction> versionCodeActions(CodeActionParams params) {
         }
         Optional<Diagnostic> updateVersionDiagnostic = params.getContext().getDiagnostics().stream()
                 .filter(diagnosticCodePredicate(SmithyDiagnostics.UPDATE_VERSION)).findFirst();
-        if (updateVersionDiagnostic.isPresent()) {
-            actions.add(
-                UpdateVersionCodeAction.build(fileUri, updateVersionDiagnostic.get().getRange())
-            );
-        }
+        updateVersionDiagnostic.ifPresent(diagnostic -> actions.add(
+                UpdateVersionCodeAction.build(fileUri, diagnostic.getRange())));
 
         return actions;
     }

src/main/java/software/amazon/smithy/lsp/codeactions/UpdateVersionCodeAction.java

@@ -15,7 +15,6 @@
 
 package software.amazon.smithy.lsp.codeactions;
 
-import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import org.eclipse.lsp4j.CodeAction;
@@ -41,7 +40,7 @@ public static CodeAction build(String fileUri, Range versionStatementRange) {
         codeAction.setKind(SmithyCodeActions.SMITHY_UPDATE_VERSION);
         WorkspaceEdit wEdit = new WorkspaceEdit();
         TextEdit edit = new TextEdit(versionStatementRange, "$version: \"" + LATEST_VERSION + "\"");
-        Map<String, List<TextEdit>> changes = Collections.singletonMap(fileUri, Collections.singletonList(edit));
+        Map<String, List<TextEdit>> changes = Map.of(fileUri, List.of(edit));
         wEdit.setChanges(changes);
         codeAction.setEdit(wEdit);
         return codeAction;

src/main/java/software/amazon/smithy/lsp/document/Document.java

@@ -23,10 +23,12 @@
 public final class Document {
     private final StringBuilder buffer;
     private int[] lineIndices;
+    private int changeVersion;
 
-    private Document(StringBuilder buffer, int[] lineIndices) {
+    private Document(StringBuilder buffer, int[] lineIndices, int changeVersion) {
         this.buffer = buffer;
         this.lineIndices = lineIndices;
+        this.changeVersion = changeVersion;
     }
 
     /**
@@ -36,14 +38,14 @@ private Document(StringBuilder buffer, int[] lineIndices) {
     public static Document of(String string) {
         StringBuilder buffer = new StringBuilder(string);
         int[] lineIndicies = computeLineIndicies(buffer);
-        return new Document(buffer, lineIndicies);
+        return new Document(buffer, lineIndicies, 0);
     }
 
     /**
      * @return A copy of this document
      */
     public Document copy() {
-        return new Document(new StringBuilder(copyText()), lineIndices.clone());
+        return new Document(new StringBuilder(copyText()), lineIndices.clone(), changeVersion);
     }
 
     /**
@@ -72,6 +74,14 @@ public void applyEdit(Range range, String text) {
         this.lineIndices = computeLineIndicies(buffer);
     }
 
+    public int changeVersion() {
+        return changeVersion;
+    }
+
+    public void bumpVersion(int to) {
+        changeVersion = to;
+    }
+
     /**
      * @return The range of the document, from (0, 0) to {@link #end()}
      */
@@ -97,20 +107,31 @@ public int indexOfLine(int line) {
      *  doesn't exist
      */
     public int lineOfIndex(int idx) {
-        // TODO: Use binary search or similar
-        if (idx >= length() || idx < 0) {
-            return -1;
-        }
-
-        for (int line = 0; line <= lastLine() - 1; line++) {
-            int currentLineIdx = indexOfLine(line);
-            int nextLineIdx = indexOfLine(line + 1);
-            if (idx >= currentLineIdx && idx < nextLineIdx) {
-                return line;
+        int low = 0;
+        int up = lastLine();
+
+        while (low <= up) {
+            int mid = (low + up) / 2;
+            int midLineIdx = lineIndices[mid];
+            int midLineEndIdx = lineEndUnchecked(mid);
+            if (idx >= midLineIdx && idx <= midLineEndIdx) {
+                return mid;
+            } else if (idx < midLineIdx) {
+                up = mid - 1;
+            } else {
+                low = mid + 1;
             }
         }
 
-        return lastLine();
+        return -1;
+    }
+
+    private int lineEndUnchecked(int line) {
+        if (line == lastLine()) {
+            return length() - 1;
+        } else {
+            return lineIndices[line + 1] - 1;
+        }
     }
 
     /**
@@ -167,6 +188,34 @@ public Position positionAtIndex(int index) {
         return new Position(line, character);
     }
 
+    /**
+     * @param start The start character offset
+     * @param end The end character offset
+     * @return The range between the two given offsets
+     */
+    public Range rangeBetween(int start, int end) {
+        if (end < start || start < 0) {
+            return null;
+        }
+
+        // The start is inclusive, so it should be within the bounds of the document
+        Position startPos = positionAtIndex(start);
+        if (startPos == null) {
+            return null;
+        }
+
+        Position endPos;
+        if (end == length()) {
+            int lastLine = lastLine();
+            int lastCol = length() - lineIndices[lastLine];
+            endPos = new Position(lastLine, lastCol);
+        } else {
+            endPos = positionAtIndex(end);
+        }
+
+        return new Range(startPos, endPos);
+    }
+
     /**
      * @param line The line to find the end of
      * @return The index of the end of the given line, or {@code -1} if the
@@ -322,7 +371,7 @@ public CharBuffer borrowId(Position position) {
         if (id == null) {
             return null;
         }
-        return id.borrowIdValue();
+        return id.idSlice();
     }
 
     /**

src/main/java/software/amazon/smithy/lsp/document/DocumentId.java

@@ -13,7 +13,7 @@
  * inaccurate in the sense that the string value it references isn't
  * necessarily a valid identifier, it just looks like an identifier.
  */
-public final class DocumentId {
+public record DocumentId(Type type, CharBuffer idSlice, Range range) {
     /**
      * Represents the different kinds of identifiers that can be used to match.
      */
@@ -41,32 +41,10 @@ public enum Type {
         /**
          * Same as {@link Type#ID}, but with a member - will have a {@code $}.
          */
-        RELATIVE_WITH_MEMBER;
-    }
-
-    private final Type type;
-    private final CharBuffer buffer;
-    private final Range range;
-
-    DocumentId(Type type, CharBuffer buffer, Range range) {
-        this.type = type;
-        this.buffer = buffer;
-        this.range = range;
-    }
-
-    public Type type() {
-        return type;
+        RELATIVE_WITH_MEMBER
     }
 
     public String copyIdValue() {
-        return buffer.toString();
-    }
-
-    public CharBuffer borrowIdValue() {
-        return buffer;
-    }
-
-    public Range range() {
-        return range;
+        return idSlice.toString();
     }
 }

src/main/java/software/amazon/smithy/lsp/document/DocumentImports.java

@@ -10,28 +10,8 @@
 
 /**
  * The imports of a document, including the range they occupy.
+ *
+ * @param importsRange The range of the imports
+ * @param imports The set of imported shape ids. They are not guaranteed to be valid shape ids
  */
-public final class DocumentImports {
-    private final Range importsRange;
-    private final Set<String> imports;
-
-    DocumentImports(Range importsRange, Set<String> imports) {
-        this.importsRange = importsRange;
-        this.imports = imports;
-    }
-
-    /**
-     * @return The range of the imports
-     */
-    public Range importsRange() {
-        return importsRange;
-    }
-
-    /**
-     * @return The set of imported shape ids. They are not guaranteed
-     *  to be valid shape ids
-     */
-    public Set<String> imports() {
-        return imports;
-    }
-}
+public record DocumentImports(Range importsRange, Set<String> imports) {}

src/main/java/software/amazon/smithy/lsp/document/DocumentNamespace.java

@@ -9,28 +9,8 @@
 
 /**
  * The namespace of the document, including the range it occupies.
+ *
+ * @param statementRange The range of the statement, including {@code namespace}
+ * @param namespace The namespace of the document. Not guaranteed to be a valid namespace
  */
-public final class DocumentNamespace {
-    private final Range statementRange;
-    private final CharSequence namespace;
-
-    DocumentNamespace(Range statementRange, CharSequence namespace) {
-        this.statementRange = statementRange;
-        this.namespace = namespace;
-    }
-
-    /**
-     * @return The range of the statement, including {@code namespace}
-     */
-    public Range statementRange() {
-        return statementRange;
-    }
-
-    /**
-     * @return The namespace of the document. Not guaranteed to be
-     *  a valid namespace
-     */
-    public CharSequence namespace() {
-        return namespace;
-    }
-}
+public record DocumentNamespace(Range statementRange, CharSequence namespace) {}