WIP: Capture all comments in parser

modules/nf-lang/src/main/antlr/ScriptLexer.g4

@@ -54,6 +54,10 @@ options {
     superClass = AbstractLexer;
 }
 
+channels {
+    COMMENT // The COMMENT channel will contain all comments, and are separatly introduced into the AST during creation
+}
+
 @header {
 package nextflow.script.parser;
 
@@ -830,18 +834,18 @@ NL  : LineTerminator   /* { this.ignoreTokenInsideParens(); } */
 
 // Multiple-line comments (including groovydoc comments)
 ML_COMMENT
-    :   '/*' .*? '*/'       /* { this.ignoreMultiLineCommentConditionally(); } */ -> type(NL)
+    :   '/*' .*? '*/'       /* { this.ignoreMultiLineCommentConditionally(); } */ -> channel(COMMENT)
     ;
 
 // Single-line comments
 SL_COMMENT
-    :   '//' ~[\r\n\uFFFF]* /* { this.ignoreTokenInsideParens(); } */             -> type(NL)
+    :   '//' ~[\r\n\uFFFF]* /* { this.ignoreTokenInsideParens(); } */             -> channel(COMMENT)
     ;
 
 // Script-header comments.
 // The very first characters of the file may be "#!".  If so, ignore the first line.
 SH_COMMENT
-    :   '#!' { require(errorIgnored || 0 == this.tokenIndex, "Shebang comment should appear at the first line", -2, true); } ShCommand (LineTerminator '#!' ShCommand)* -> type(NL)
+    :   '#!' { require(errorIgnored || 0 == this.tokenIndex, "Shebang comment should appear at the first line", -2, true); } ShCommand (LineTerminator '#!' ShCommand)* -> channel(COMMENT)
     ;
 
 // Unexpected characters will be handled by groovy parser later.

modules/nf-lang/src/main/antlr/ScriptParser.g4

@@ -211,7 +211,7 @@ processWhen
     ;
 
 processExec
-    :   (SCRIPT | SHELL | EXEC) COLON nls blockStatements
+    :   execType=(SCRIPT | SHELL | EXEC) COLON nls blockStatements
     ;
 
 processStub

modules/nf-lang/src/main/java/nextflow/script/ast/WorkflowNode.java

@@ -45,15 +45,22 @@ public class WorkflowNode extends MethodNode {
     public final Statement publishers;
 
     public WorkflowNode(String name, Statement takes, Statement main, Statement emits, Statement publishers) {
-        super(name, 0, dummyReturnType(emits), dummyParams(takes), ClassNode.EMPTY_ARRAY, EmptyStatement.INSTANCE);
+        super(
+            name != null ? name : "", // getText causes an exception if name is null, ugly hack for now
+            0,
+            dummyReturnType(emits),
+            dummyParams(takes),
+            ClassNode.EMPTY_ARRAY,
+            EmptyStatement.INSTANCE
+        );
         this.takes = takes;
         this.main = main;
         this.emits = emits;
         this.publishers = publishers;
     }
 
     public boolean isEntry() {
-        return getName() == null;
+        return getName() == "";
     }
 
     public boolean isCodeSnippet() {

modules/nf-lang/src/main/java/nextflow/script/control/Compiler.java

@@ -99,8 +99,10 @@ public void compile(SourceUnit source) {
             source.buildAST();
         }
         catch( RecognitionException e ) {
+            System.err.println("RecognitionException: " + e.getMessage());
         }
         catch( CompilationFailedException e ) {
+            System.err.println("CompilationFailedException: " + e.getMessage());
         }
     }