refactor: remove startTagPosition

`startTagPosition` is part of the API of sax but was removed from the API when
saxes was forked. Its only remaining use was to produce padding when running
into an error case. This would allow producing a more representative text node
but accurrate data after an error is not part of saxes' contract. So the padding
has been removed and `startTagPosition` too.

lib/saxes.js

@@ -305,8 +305,6 @@ class SaxesParser {
       this.ns = Object.assign({}, rootNS);
     }
 
-    this.startTagPosition = undefined;
-
     this.trackPosition = this.opt.position !== false;
     if (this.trackPosition) {
       /** The line number the parser is  currently looking at. */
@@ -629,7 +627,6 @@ class SaxesParser {
     }
     if (c === LESS) {
       this.state = S_OPEN_WAKA;
-      this.startTagPosition = this.position;
     }
     else {
       // have to process this as a text node.
@@ -678,7 +675,6 @@ class SaxesParser {
     switch (c) {
     case LESS:
       this.state = S_OPEN_WAKA;
-      this.startTagPosition = this.position;
       break;
     case AMP:
       this.state = S_ENTITY;
@@ -714,17 +710,11 @@ class SaxesParser {
         this.state = S_PI;
         this.piTarget = this.piBody = "";
         break;
-      default: {
+      default:
         this.fail("disallowed characer in tag name.");
-        // if there was some whitespace, then add that in.
-        const pad = (this.startTagPosition + 1 < this.position) ?
-              new Array(this.position - this.startTagPosition).join(" ") :
-              "";
-        this.textNode += `<${pad}${String.fromCodePoint(c)}`;
         this.state = S_TEXT;
         this.xmlDeclPossible = false;
       }
-      }
     }
   }
 

test/parser-position.js

@@ -25,19 +25,19 @@ describe("parser position", () => {
   testPosition(
     "with single chunk",
     ["<div>abcdefgh</div>"], [
-      ["opentagstart", { position: 5, startTagPosition: 1 }],
-      ["opentag", { position: 5, startTagPosition: 1 }],
-      ["text", { position: 19, startTagPosition: 14 }],
-      ["closetag", { position: 19, startTagPosition: 14 }],
+      ["opentagstart", { position: 5 }],
+      ["opentag", { position: 5 }],
+      ["text", { position: 19 }],
+      ["closetag", { position: 19 }],
     ]);
 
   testPosition(
     "with multiple chunks",
     ["<div>abcde", "fgh</div>"], [
-      ["opentagstart", { position: 5, startTagPosition: 1 }],
-      ["opentag", { position: 5, startTagPosition: 1 }],
-      ["text", { position: 19, startTagPosition: 14 }],
-      ["closetag", { position: 19, startTagPosition: 14 }],
+      ["opentagstart", { position: 5 }],
+      ["opentag", { position: 5 }],
+      ["text", { position: 19 }],
+      ["closetag", { position: 19 }],
     ]);
 
   test({