Adds a parseSingle() method for the parser

Moves parser builder as nested class of parser

partiql-cli/src/main/kotlin/org/partiql/cli/pipeline/Pipeline.kt

@@ -4,7 +4,6 @@ import org.partiql.ast.v1.Statement
 import org.partiql.cli.ErrorCodeString
 import org.partiql.eval.Mode
 import org.partiql.eval.compiler.PartiQLCompiler
-import org.partiql.parser.PartiQLParserBuilderV1
 import org.partiql.parser.PartiQLParserV1
 import org.partiql.plan.Plan
 import org.partiql.planner.PartiQLPlanner
@@ -35,10 +34,7 @@ internal class Pipeline private constructor(
 
     private fun parse(source: String): Statement {
         val result = listen(ctx.errorListener as AppPErrorListener) {
-            parser.parse(source, ctx)
-        }
-        if (result.statements.size != 1) {
-            throw PipelineException("Expected exactly one statement, got: ${result.statements.size}")
+            parser.parseSingle(source, ctx)
         }
         return result.statements[0]
     }
@@ -83,7 +79,7 @@ internal class Pipeline private constructor(
         private fun create(mode: Mode, out: PrintStream, config: Config): Pipeline {
             val listener = config.getErrorListener(out)
             val ctx = Context.of(listener)
-            val parser = PartiQLParserBuilderV1().build()
+            val parser = PartiQLParserV1.Builder().build()
             val planner = PartiQLPlanner.builder().build()
             val compiler = PartiQLCompiler.builder().build()
             return Pipeline(parser, planner, compiler, ctx, mode)

partiql-parser/api/partiql-parser.api

@@ -16,18 +16,19 @@ public class org/partiql/parser/PartiQLParserBuilder {
 	public fun build ()Lorg/partiql/parser/PartiQLParser;
 }
 
-public class org/partiql/parser/PartiQLParserBuilderV1 {
-	public fun <init> ()V
-	public fun build ()Lorg/partiql/parser/PartiQLParserV1;
-}
-
 public abstract interface class org/partiql/parser/PartiQLParserV1 {
-	public static fun builder ()Lorg/partiql/parser/PartiQLParserBuilderV1;
+	public static fun builder ()Lorg/partiql/parser/PartiQLParserV1$Builder;
 	public fun parse (Ljava/lang/String;)Lorg/partiql/parser/PartiQLParserV1$Result;
 	public abstract fun parse (Ljava/lang/String;Lorg/partiql/spi/Context;)Lorg/partiql/parser/PartiQLParserV1$Result;
+	public fun parseSingle (Ljava/lang/String;Lorg/partiql/spi/Context;)Lorg/partiql/parser/PartiQLParserV1$Result;
 	public static fun standard ()Lorg/partiql/parser/PartiQLParserV1;
 }
 
+public class org/partiql/parser/PartiQLParserV1$Builder {
+	public fun <init> ()V
+	public fun build ()Lorg/partiql/parser/PartiQLParserV1;
+}
+
 public final class org/partiql/parser/PartiQLParserV1$Result {
 	public field locations Lorg/partiql/spi/SourceLocations;
 	public field statements Ljava/util/List;

partiql-parser/src/main/java/org/partiql/parser/PartiQLParserV1.java

@@ -18,10 +18,17 @@
 import org.partiql.ast.v1.Statement;
 import org.partiql.parser.internal.PartiQLParserDefaultV1;
 import org.partiql.spi.Context;
+import org.partiql.spi.SourceLocation;
 import org.partiql.spi.SourceLocations;
+import org.partiql.spi.errors.PError;
+import org.partiql.spi.errors.PErrorKind;
 import org.partiql.spi.errors.PErrorListenerException;
+import org.partiql.spi.errors.Severity;
 
+import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 /**
  * TODO: Rename to PartiQLParser
@@ -34,10 +41,40 @@ public interface PartiQLParserV1 {
      * @param ctx a configuration object for the parser
      * @throws PErrorListenerException when the [org.partiql.spi.errors.PErrorListener] defined in the [ctx] throws an
      * [PErrorListenerException], this method halts execution and propagates the exception.
+     * @see PartiQLParserV1#parseSingle(String, Context)
      */
     @NotNull
     Result parse(@NotNull String source, @NotNull Context ctx) throws PErrorListenerException;
 
+    /**
+     * TODO
+     * @param source TODO
+     * @param ctx TODO
+     * @return TODO
+     * @throws PErrorListenerException TODO
+     * @see PartiQLParserV1#parse(String, Context)
+     */
+    @NotNull
+    default Result parseSingle(@NotNull String source, @NotNull Context ctx) throws PErrorListenerException {
+        Result result = parse(source, ctx);
+        if (result.statements.size() != 1) {
+            SourceLocation location;
+            if (result.statements.size() > 1) {
+                location = result.locations.get(result.statements.get(1).tag);
+            } else {
+                location = null;
+            }
+            Map<String, Object> properties = new HashMap<String, Object>() {{
+                put("EXPECTED_TOKENS", new ArrayList<String>() {{
+                    add("EOF");
+                }});
+            }};
+            PError pError = new PError(PError.UNEXPECTED_TOKEN, Severity.ERROR(), PErrorKind.SYNTAX(), location, properties);
+            ctx.getErrorListener().report(pError);
+        }
+        return result;
+    }
+
     /**
      * Parses the [source] into an AST.
      * @param source the user's input
@@ -82,8 +119,8 @@ public Result(@NotNull List<Statement> statements, @NotNull SourceLocations loca
      * @return TODO
      */
     @NotNull
-    public static PartiQLParserBuilderV1 builder() {
-        return new PartiQLParserBuilderV1();
+    public static Builder builder() {
+        return new Builder();
     }
 
     /**
@@ -94,4 +131,21 @@ public static PartiQLParserBuilderV1 builder() {
     public static PartiQLParserV1 standard() {
         return new PartiQLParserDefaultV1();
     }
+
+    /**
+     * A builder class to instantiate a {@link PartiQLParserV1}.
+     */
+    public class Builder {
+        // TODO: Can this be replaced with Lombok?
+        // TODO: https://github.com/partiql/partiql-lang-kotlin/issues/1632
+
+        /**
+         * TODO
+         * @return TODO
+         */
+        @NotNull
+        public PartiQLParserV1 build() {
+            return new PartiQLParserDefaultV1();
+        }
+    }
 }

partiql-planner/src/test/kotlin/org/partiql/planner/PlannerPErrorReportingTests.kt

@@ -3,7 +3,7 @@ package org.partiql.planner
 import org.junit.jupiter.params.ParameterizedTest
 import org.junit.jupiter.params.provider.MethodSource
 import org.partiql.ast.v1.Statement
-import org.partiql.parser.PartiQLParserBuilderV1
+import org.partiql.parser.PartiQLParserV1
 import org.partiql.plan.Operation
 import org.partiql.planner.internal.typer.CompilerType
 import org.partiql.planner.internal.typer.PlanTyper.Companion.toCType
@@ -42,7 +42,7 @@ internal class PlannerPErrorReportingTests {
         .catalogs(catalog)
         .build()
 
-    private val parser = PartiQLParserBuilderV1().build()
+    private val parser = PartiQLParserV1.Builder().build()
 
     private val statement: ((String) -> Statement) = { query ->
         val parseResult = parser.parse(query)