Merge pull request #40 from drgrice1/parentheses-issues

Add some more cases where parentheses are needed in text output.

Author: pstaabp

package.json

@@ -1,7 +1,7 @@
 {
 	"name": "@openwebwork/mathquill",
 	"description": "Easily type math in your webapp",
-	"version": "0.11.0",
+	"version": "0.11.1",
 	"license": "MPL-2.0",
 	"repository": {
 		"type": "git",

src/commands/math/commands.ts

@@ -305,7 +305,7 @@ const FractionChooseCreateLeftOfMixin = <TBase extends Constructor<MathCommand>>
 				while (
 					leftward &&
 					!(
-						leftward instanceof BinaryOperator ||
+						(leftward instanceof BinaryOperator && !(leftward instanceof LatexCmds.factorial)) ||
 						('text' in LatexCmds && leftward instanceof LatexCmds.text) ||
 						leftward instanceof UpperLowerLimitCommand ||
 						leftward.ctrlSeq === '\\ ' ||

src/commands/mathElements.ts

@@ -716,11 +716,13 @@ export class Fraction extends MathCommand {
 			let numBlocks = 0;
 			let haveDigits = false;
 			let numPeriods = 0;
+			let newBlock = false;
 			this.ends[dir]?.eachChild((child: TNode) => {
 				if (child instanceof Digit) haveDigits = true;
 				if (child instanceof VanillaSymbol && child.ctrlSeq === '.') ++numPeriods;
 
 				if (
+					newBlock ||
 					!(
 						child instanceof Digit ||
 						(child instanceof VanillaSymbol && child.ctrlSeq === '.' && numPeriods < 2 && !numBlocks) ||
@@ -730,6 +732,11 @@ export class Fraction extends MathCommand {
 				)
 					++numBlocks;
 
+				// These are things that terminate a block.  Anything typed after them
+				// starts a new block and increments the block count above.
+				newBlock =
+					('factorial' in LatexCmds && child instanceof LatexCmds.factorial) || child instanceof SupSub;
+
 				if (
 					(haveDigits && numBlocks) ||
 					numBlocks > 1 ||
@@ -838,11 +845,13 @@ export const supSubText = (prefix: string, block?: TNode) => {
 	let numBlocks = 0;
 	let haveDigits = false;
 	let numPeriods = 0;
+	let newBlock = false;
 	block?.eachChild((child: TNode) => {
 		if (child instanceof Digit) haveDigits = true;
 		if (child instanceof VanillaSymbol && child.ctrlSeq === '.') ++numPeriods;
 
 		if (
+			newBlock ||
 			!(
 				child instanceof Digit ||
 				(child instanceof VanillaSymbol && child.ctrlSeq === '.' && numPeriods < 2 && !numBlocks) ||
@@ -851,6 +860,10 @@ export const supSubText = (prefix: string, block?: TNode) => {
 		)
 			++numBlocks;
 
+		// These are things that terminate a block.  Anything typed after them
+		// starts a new block and increments the block count above.
+		newBlock = 'factorial' in LatexCmds && child instanceof LatexCmds.factorial;
+
 		if (
 			(haveDigits && numBlocks) ||
 			numBlocks > 1 ||