Convert src/core/type1_font.js to use standard classes

src/core/type1_font.js

@@ -30,9 +30,7 @@ import { Stream } from "./stream.js";
 import { Type1Parser } from "./type1_parser.js";
 import { warn } from "../shared/util.js";
 
-// Type1Font is also a CIDFontType0.
-const Type1Font = (function Type1FontClosure() {
-  function findBlock(streamBytes, signature, startIndex) {
+function findBlock(streamBytes, signature, startIndex) {
   const streamBytesLength = streamBytes.length;
   const signatureLength = signature.length;
   const scanLength = streamBytesLength - signatureLength;
@@ -59,9 +57,9 @@ const Type1Font = (function Type1FontClosure() {
     found,
     length: i,
   };
-  }
+}
 
-  function getHeaderBlock(stream, suggestedLength) {
+function getHeaderBlock(stream, suggestedLength) {
   const EEXEC_SIGNATURE = [0x65, 0x65, 0x78, 0x65, 0x63];
 
   const streamStartPos = stream.pos; // Save the initial stream position.
@@ -128,9 +126,9 @@ const Type1Font = (function Type1FontClosure() {
     stream: new Stream(stream.getBytes(suggestedLength)),
     length: suggestedLength,
   };
-  }
+}
 
-  function getEexecBlock(stream, suggestedLength) {
+function getEexecBlock(stream, suggestedLength) {
   // We should ideally parse the eexec block to ensure that `suggestedLength`
   // is correct, so we don't truncate the block data if it's too small.
   // However, this would also require checking if the fixed-content portion
@@ -149,10 +147,13 @@ const Type1Font = (function Type1FontClosure() {
     stream: new Stream(eexecBytes),
     length: eexecBytes.length,
   };
-  }
+}
 
-  // eslint-disable-next-line no-shadow
-  function Type1Font(name, file, properties) {
+/**
+ * Type1Font is also a CIDFontType0.
+ */
+class Type1Font {
+  constructor(name, file, properties) {
     // Some bad generators embed pfb file as is, we have to strip 6-byte header.
     // Also, length1 and length2 might be off by 6 bytes as well.
     // http://www.math.ubc.ca/~cass/piscript/type1.pdf
@@ -215,21 +216,20 @@ const Type1Font = (function Type1FontClosure() {
     this.seacs = this.getSeacs(data.charstrings);
   }
 
-  Type1Font.prototype = {
   get numGlyphs() {
     return this.charstrings.length + 1;
-    },
+  }
 
-    getCharset: function Type1Font_getCharset() {
+  getCharset() {
     const charset = [".notdef"];
     const charstrings = this.charstrings;
     for (let glyphId = 0; glyphId < charstrings.length; glyphId++) {
       charset.push(charstrings[glyphId].glyphName);
     }
     return charset;
-    },
+  }
 
-    getGlyphMapping: function Type1Font_getGlyphMapping(properties) {
+  getGlyphMapping(properties) {
     const charstrings = this.charstrings;
 
     if (properties.composite) {
@@ -264,9 +264,9 @@ const Type1Font = (function Type1FontClosure() {
     }
 
     return type1FontGlyphMapping(properties, builtInEncoding, glyphNames);
-    },
+  }
 
-    hasGlyphId: function Type1Font_hasGlyphID(id) {
+  hasGlyphId(id) {
     if (id < 0 || id >= this.numGlyphs) {
       return false;
     }
@@ -276,12 +276,11 @@ const Type1Font = (function Type1FontClosure() {
     }
     const glyph = this.charstrings[id - 1];
     return glyph.charstring.length > 0;
-    },
+  }
 
-    getSeacs: function Type1Font_getSeacs(charstrings) {
-      let i, ii;
+  getSeacs(charstrings) {
     const seacMap = [];
-      for (i = 0, ii = charstrings.length; i < ii; i++) {
+    for (let i = 0, ii = charstrings.length; i < ii; i++) {
       const charstring = charstrings[i];
       if (charstring.seac) {
         // Offset by 1 for .notdef
@@ -289,19 +288,17 @@ const Type1Font = (function Type1FontClosure() {
       }
     }
     return seacMap;
-    },
+  }
 
-    getType2Charstrings: function Type1Font_getType2Charstrings(
-      type1Charstrings
-    ) {
+  getType2Charstrings(type1Charstrings) {
     const type2Charstrings = [];
     for (let i = 0, ii = type1Charstrings.length; i < ii; i++) {
       type2Charstrings.push(type1Charstrings[i].charstring);
     }
     return type2Charstrings;
-    },
+  }
 
-    getType2Subrs: function Type1Font_getType2Subrs(type1Subrs) {
+  getType2Subrs(type1Subrs) {
     let bias = 0;
     const count = type1Subrs.length;
     if (count < 1133) {
@@ -324,15 +321,9 @@ const Type1Font = (function Type1FontClosure() {
     }
 
     return type2Subrs;
-    },
+  }
 
-    wrap: function Type1Font_wrap(
-      name,
-      glyphs,
-      charstrings,
-      subrs,
-      properties
-    ) {
+  wrap(name, glyphs, charstrings, subrs, properties) {
     const cff = new CFF();
     cff.header = new CFFHeader(1, 0, 4, 4);
 
@@ -427,10 +418,7 @@ const Type1Font = (function Type1FontClosure() {
 
     const compiler = new CFFCompiler(cff);
     return compiler.compile();
-    },
-  };
-
-  return Type1Font;
-})();
+  }
+}
 
 export { Type1Font };