Split the library into smaller files

source/build-type-graph.js

@@ -0,0 +1,93 @@
+//reserved keywords that can't be used as identifiers
+const keywords = require('./keywords.json');
+const { eatBlock, checkAlphaNumeric } = require('./utils');
+const parseInput = require('./parse-input');
+
+//parse the schema into a type graph
+const buildTypeGraph = (schema, options) => {
+	//the default graph
+	let graph = {
+		String: { scalar: true },
+		Integer: { scalar: true },
+		Float: { scalar: true },
+		Boolean: { scalar: true },
+	};
+
+	//parse the schema
+	const tokens = parseInput(schema, false, options);
+	let pos = 0;
+
+	while (tokens[pos++]) {
+		//check for keywords
+		switch(tokens[pos - 1]) {
+			case 'type':
+				graph[tokens[pos++]] = parseCompoundType(tokens, pos, options);
+
+				//advance to the end of the compound type
+				pos = eatBlock(tokens, pos);
+
+				break;
+
+			case 'scalar':
+				if (keywords.includes(graph[tokens[pos - 1]])) {
+					throw 'Unexpected keyword ' + graph[tokens[pos - 1]];
+				}
+
+				graph[tokens[pos++]] = { scalar: true };
+				break;
+
+			default:
+				throw 'Unknown token ' + tokens[pos - 1];
+		}
+	}
+
+	if (options.debug) {
+		console.log('Type Graph:\n', graph, '\n');
+	}
+
+	return graph;
+};
+
+//moved this routine to a separate function for clarity
+const parseCompoundType = (tokens, pos, options) => {
+	//format check (not strictly necessary, but it looks nice)
+	if (tokens[pos] !== '{') {
+		throw 'Expected \'{\' in compound type definition';
+	}
+
+	//graph component to be returned
+	const compound = {};
+
+	//for each line of the compound type
+	while (tokens[pos++] && tokens[pos] !== '}') {
+		let type = tokens[pos++];
+		const name = tokens[pos];
+
+		//no mangled types or names
+		checkAlphaNumeric(type);
+		checkAlphaNumeric(name);
+
+		//can't use keywords
+		if (keywords.includes(type) || keywords.includes(name)) {
+			throw 'Unexpected keyword found as type field or type name (' + type + ' ' + name + ')';
+		}
+
+		//check for duplicate fields
+		if (Object.keys(compound).includes(name)) {
+			throw 'Unexpected duplicate field name';
+		}
+
+		//finally, push to the compound definition
+		compound[name] = {
+			typeName: type
+		};
+	}
+
+	if (options.debug) {
+		console.log('Compound Type:\n', compound, '\n');
+	}
+
+	return compound;
+};
+
+module.exports = buildTypeGraph;