Execute unfinished statements in cypher shell non interactive and file mode

Fixes a bug in cypher shell where unfinished statements were not executed
in non interactive and file mode. This lead to quietly ignoring the last
statement if it was not semicolon terminated.

Co-authored-by: AakashSorathiya <[email protected]>

Author: loveleif

cypher-shell/src/main/java/org/neo4j/shell/cli/NonInteractiveShellRunner.java

@@ -77,6 +77,10 @@ public int runUntilEnd()
         }
 
         int exitCode = 0;
+
+        // Executing this could fail but we try anyway to avoid hiding errors
+        statementParser.incompleteStatement().ifPresent( statements::add );
+
         for ( String statement : statements )
         {
             try

cypher-shell/src/main/java/org/neo4j/shell/parser/ShellStatementParser.java

@@ -292,4 +292,11 @@ public void reset()
         parsedStatements.clear();
         awaitedRightDelimiter = Optional.empty();
     }
+
+    @Nonnull
+    @Override
+    public Optional<String> incompleteStatement()
+    {
+        return Optional.of( statement.toString().trim() ).filter( s -> !s.isEmpty() );
+    }
 }

cypher-shell/src/main/java/org/neo4j/shell/parser/StatementParser.java

@@ -20,6 +20,7 @@
 package org.neo4j.shell.parser;
 
 import java.util.List;
+import java.util.Optional;
 import javax.annotation.Nonnull;
 
 /**
@@ -58,4 +59,12 @@ public interface StatementParser
      * Reset the state of the Parser, removing any and all state it has.
      */
     void reset();
+
+    /**
+     * Returns any incomplete statement.
+     *
+     * @return the statement that is currently being parsed but has not completed, if any
+     */
+    @Nonnull
+    Optional<String> incompleteStatement();
 }

cypher-shell/src/test/java/org/neo4j/shell/cli/NonInteractiveShellRunnerTest.java

@@ -181,4 +181,22 @@ public void nonInteractiveHasNoHistory() throws Exception
         // when then
         assertEquals( Historian.empty, runner.getHistorian() );
     }
+
+    @Test
+    public void shouldTryToExecuteIncompleteStatements() throws CommandException
+    {
+        String input = "good1;\nno semicolon here\n// A comment at end";
+        NonInteractiveShellRunner runner = new NonInteractiveShellRunner(
+                FailBehavior.FAIL_FAST,
+                cmdExecuter,
+                logger, statementParser,
+                new ByteArrayInputStream( input.getBytes() ) );
+        int code = runner.runUntilEnd();
+
+        assertEquals( "Exit code incorrect", 0, code );
+        verify( logger, times( 0 ) ).printError( anyString() );
+        verify( cmdExecuter ).execute( "good1;" );
+        verify( cmdExecuter ).execute( "no semicolon here" );
+        verifyNoMoreInteractions( cmdExecuter );
+    }
 }