feat(dms): cleanup edge cases

Author: arnog

src/compute-engine/latex-syntax/dictionary/definitions-units.ts

@@ -39,7 +39,7 @@ import {
   parseUnitDSL,
   type UnitExpression,
 } from '../../numerics/unit-data';
-import { normalizeAngle, degreesToDMS } from '../serialize-dms';
+import { normalizeAngle, formatDMS } from '../serialize-dms';
 
 // ---------------------------------------------------------------------------
 // Helpers
@@ -380,7 +380,8 @@ export const DEFINITIONS_UNITS: LatexDictionary = [
 
       if (
         isAngleUnit &&
-        (options.dmsFormat || options.angleNormalization !== 'none')
+        (options.dmsFormat ||
+          (options.angleNormalization && options.angleNormalization !== 'none'))
       ) {
         // Get numeric value
         const magnitudeValue = machineValue(magnitude);
@@ -403,33 +404,11 @@ export const DEFINITIONS_UNITS: LatexDictionary = [
         }
 
         // Apply normalization
-        if (options.angleNormalization !== 'none') {
+        if (options.angleNormalization && options.angleNormalization !== 'none')
           degrees = normalizeAngle(degrees, options.angleNormalization);
-        }
 
-        // Format as DMS if requested
-        if (options.dmsFormat) {
-          const { deg, min, sec } = degreesToDMS(degrees);
-
-          let result = `${deg}°`;
-
-          if (Math.abs(sec) > 0.001) {
-            // Include seconds
-            const secStr = sec % 1 === 0 ? sec.toString() : sec.toFixed(2);
-            result += `${Math.abs(min)}'${Math.abs(Number(secStr))}"`;
-          } else if (Math.abs(min) > 0) {
-            // Include minutes only
-            result += `${Math.abs(min)}'`;
-          } else {
-            // Degrees only, show 0'0" for consistency
-            result += `0'0"`;
-          }
-
-          return result;
-        } else {
-          // Just normalize, use decimal degrees
-          return `${degrees}°`;
-        }
+        if (options.dmsFormat) return formatDMS(degrees);
+        return `${degrees}°`;
       }
 
       // Fall through to default Quantity serialization

src/compute-engine/latex-syntax/serialize-dms.ts

@@ -20,15 +20,15 @@ export function normalizeAngle(
   if (mode === '0...360') {
     // Normalize to [0, 360)
     const normalized = degrees % 360;
-    return normalized < 0 ? normalized + 360 : normalized;
+    return (normalized < 0 ? normalized + 360 : normalized) || 0; // Avoid -0
   }
 
   if (mode === '-180...180') {
     // Normalize to [-180, 180]
     let normalized = degrees % 360;
     if (normalized > 180) normalized -= 360;
     if (normalized < -180) normalized += 360;
-    return normalized;
+    return normalized || 0; // Avoid -0
   }
 
   return degrees;
@@ -54,7 +54,7 @@ export function degreesToDMS(totalDegrees: number): DMSComponents {
   let finalMin = min;
   let finalDeg = deg;
 
-  if (sec >= 59.999) {
+  if (sec >= 60) {
     sec = 0;
     finalMin++;
   }
@@ -66,8 +66,29 @@ export function degreesToDMS(totalDegrees: number): DMSComponents {
   }
 
   return {
-    deg: sign * finalDeg,
-    min: sign * finalMin,
-    sec: sec === 0 ? 0 : sign * sec, // Avoid -0
+    deg: sign * finalDeg || 0, // Avoid -0
+    min: sign * finalMin || 0, // Avoid -0
+    sec: sec === 0 ? 0 : sign * sec,
   };
 }
+
+/**
+ * Format a decimal degree value as a DMS LaTeX string.
+ * Used by both Degrees and Quantity serializers.
+ */
+export function formatDMS(degrees: number): string {
+  const { deg, min, sec } = degreesToDMS(degrees);
+
+  let result = `${deg}°`;
+
+  if (Math.abs(sec) > 0.001) {
+    const secStr = sec % 1 === 0 ? sec.toString() : sec.toFixed(2);
+    result += `${Math.abs(min)}'${Math.abs(Number(secStr))}"`;
+  } else if (Math.abs(min) > 0) {
+    result += `${Math.abs(min)}'`;
+  } else {
+    result += `0'0"`;
+  }
+
+  return result;
+}