920 pre push and commit hooks

.gitignore

@@ -1 +1,2 @@
 .DS_Store
+node_modules

.husky/pre-commit

@@ -0,0 +1 @@
+yarn lint-staged

.lintstagedrc.json

@@ -0,0 +1,4 @@
+{
+  "*.{js,json}": ["eslint --fix", "prettier --write --ignore-unknown"],
+  "*.{css,md,html}": ["prettier --write --ignore-unknown"]
+}

.prettierignore

@@ -0,0 +1,6 @@
+node_modules
+yarn.lock
+
+# Ignore artifacts:
+build
+coverage

.prettierrc

@@ -0,0 +1,7 @@
+{
+  "bracketSpacing": true,
+  "semi": true,
+  "singleQuote": false,
+  "tabWidth": 2,
+  "trailingComma": "es5"
+}

README.md

@@ -6,7 +6,6 @@ Unlike the original controls at https://github.com/OpenHistoricalMap/mbgl-timesl
 
 For a demonstration, see **index.html** and https://openhistoricalmap.github.io/leaflet-ohm-timeslider-v2/
 
-
 # Constructor Options
 
 `position` -- The Leaflet position for the control. Defaults to `bottomright`. It is recommended to keep this, as the control has an arrow sticking off the top/left.
@@ -31,7 +30,6 @@ For a demonstration, see **index.html** and https://openhistoricalmap.github.io/
 
 `onRangeChange: function ([date1, date2])` -- A callback function which will be called when the date range changes. The newly-available range (2-item list of ISO strings) will be passed as a param. Within the callback function, `this` will refer to the OHMTimeSlider.
 
-
 # Methods
 
 `getDate(asdecimal=false)` -- Return the currently-selected date on the slider. The date will be in ISO YYYY-MM-DD format, unless `decimaldate` is given to get it as a decimaldate number instead.
@@ -62,7 +60,6 @@ For a demonstration, see **index.html** and https://openhistoricalmap.github.io/
 
 `listLanguages()` -- Return a list of the supported language translations for use with the `language` option.
 
-
 # Development
 
 Fire up a Python CLI web server via `python -m SimpleHTTPServer 9646` or `python3 -m http.server 9646`
@@ -72,12 +69,14 @@ You can now point a browser at http://localhost:9646/ and see the demo.
 To create the minified JS/CSS files, use whatever tools you prefer such as UglifyJS and UglifyCSS.
 
 Installation:
+
 ```
 nvm use 16.9.0
 npm install uglify-js uglifycss -g
 ```
 
 Usage:
+
 ```
 uglifycss --output leaflet-ohm-timeslider.min.css leaflet-ohm-timeslider.css
 uglifyjs --keep-fargs --keep-fnames --output leaflet-ohm-timeslider.min.js leaflet-ohm-timeslider.js
@@ -130,4 +129,4 @@ We welcome PRs with new languages added to this, or if you're not sure how to do
     months: ['','',...],
     bce: "",
     dateformat: '',
-```
+```

decimaldate.js

@@ -6,160 +6,169 @@ const decimaldate = {};
 
 decimaldate.DECIMALPLACES = 6;
 
-decimaldate.RE_YEARMONTHDAY = /^(\-?\+?)(\d+)\-(\d\d)\-(\d\d)$/;
+decimaldate.RE_YEARMONTHDAY = /^(-?\+?)(\d+)-(\d\d)-(\d\d)$/;
 
 decimaldate.iso2dec = (isodate) => {
-    // parse the date into 3 integers and maybe a minus sign
-    // validate that it's a valid date
-    const datepieces = isodate.match(decimaldate.RE_YEARMONTHDAY);
-    if (! datepieces) throw new Error(`iso2dec() malformed date ${isodate}`);
-
-    const [plusminus, yearstring, monthstring, daystring] = datepieces.slice(1);
-    const monthint = parseInt(monthstring);
-    const dayint = parseInt(daystring);
-    let yearint = plusminus == '-' ? -1 * parseInt(yearstring) : parseInt(yearstring);
-    if (yearint <= 0) yearint -= 1;  // ISO 8601 shift year<=0 by 1, 0=1BCE, -1=2BCE; we want proper negative integer
-    if (! decimaldate.isvalidmonthday(yearint, monthint, dayint))  throw new Error(`iso2dec() invalid date ${isodate}`);
-
-    // number of days passed = decimal portion
-    // if BCE <=0 then count backward from the end of the year, instead of forward from January
-    const decbit = decimaldate.proportionofdayspassed(yearint, monthint, dayint);
-
-    let decimaloutput;
-    if (yearint < 0) {
-        // ISO 8601 shift year<=0 by 1, 0=1BCE, -1=2BCE; we want string version
-        // so it's 1 to get from the artificially-inflated integer (string 0000 => -1 for math, +1 to get back to 0)
-        decimaloutput = 1 + 1 + yearint - (1 - decbit);
-    }
-    else {
-        decimaloutput = yearint + decbit;
-    }
-
-    // round to standardized number of decimals
-    decimaloutput = parseFloat(decimaloutput.toFixed(decimaldate.DECIMALPLACES));
-    return decimaloutput;
+  // parse the date into 3 integers and maybe a minus sign
+  // validate that it's a valid date
+  const datepieces = isodate.match(decimaldate.RE_YEARMONTHDAY);
+  if (!datepieces) throw new Error(`iso2dec() malformed date ${isodate}`);
+
+  const [plusminus, yearstring, monthstring, daystring] = datepieces.slice(1);
+  const monthint = parseInt(monthstring, 10);
+  const dayint = parseInt(daystring, 10);
+  let yearint =
+    plusminus === "-"
+      ? -1 * parseInt(yearstring, 10)
+      : parseInt(yearstring, 10);
+  if (yearint <= 0) yearint -= 1; // ISO 8601 shift year<=0 by 1, 0=1BCE, -1=2BCE; we want proper negative integer
+  if (!decimaldate.isvalidmonthday(yearint, monthint, dayint)) {
+    throw new Error(`iso2dec() invalid date ${isodate}`);
+  }
+
+  // number of days passed = decimal portion
+  // if BCE <=0 then count backward from the end of the year, instead of forward from January
+  const decbit = decimaldate.proportionofdayspassed(yearint, monthint, dayint);
+
+  let decimaloutput;
+  if (yearint < 0) {
+    // ISO 8601 shift year<=0 by 1, 0=1BCE, -1=2BCE; we want string version
+    // so it's 1 to get from the artificially-inflated integer (string 0000 => -1 for math, +1 to get back to 0)
+    decimaloutput = 1 + 1 + yearint - (1 - decbit);
+  } else {
+    decimaloutput = yearint + decbit;
+  }
+
+  // round to standardized number of decimals
+  decimaloutput = parseFloat(decimaloutput.toFixed(decimaldate.DECIMALPLACES));
+  return decimaloutput;
 };
 
-
 decimaldate.dec2iso = (decdate) => {
-    // remove the artificial +1 that we add to make positive dates look intuitive
-    const truedecdate = decdate - 1;
-    const ispositive = truedecdate > 0;
-
-    // get the integer year
-    if (ispositive) {
-        yearint = Math.floor(truedecdate) + 1;
-    }
-    else {
-        yearint = -Math.abs(Math.floor(truedecdate));  // ISO 8601 shift and year<=0 by 1, 0=1BCE, -1=2BCE
-    }
-
-    // how many days in year X decimal portion = number of days into the year
-    // if it's <0 then we count backward from the end of the year, instead of forward into the year
-    const dty = decimaldate.daysinyear(yearint);
-    let targetday = dty * (Math.abs(truedecdate) % 1);
-    if (ispositive) targetday = Math.ceil(targetday);
-    else targetday = dty - Math.floor(targetday);
-
-    // count up days months at a time, until we reach our target month
-    // then the remainder (days) is the day of that month
-    let monthint;
-    let dayspassed = 0;
-    for (let m = 1; m <= 12; m++) {
-        monthint = m;
-        const dtm = decimaldate.daysinmonth(yearint, monthint);
-        if (dayspassed + dtm < targetday) {
-            dayspassed += dtm;
-        }
-        else {
-            break;
-        }
+  // remove the artificial +1 that we add to make positive dates look intuitive
+  const truedecdate = decdate - 1;
+  const ispositive = truedecdate > 0;
+
+  // get the integer year. (ISO 8601 shift and year<=0 by 1, 0=1BCE, -1=2BCE)
+  let yearint = ispositive
+    ? Math.floor(truedecdate) + 1
+    : -Math.abs(Math.floor(truedecdate));
+
+  // how many days in year X decimal portion = number of days into the year
+  // if it's <0 then we count backward from the end of the year, instead of forward into the year
+  const dty = decimaldate.daysinyear(yearint);
+  let targetday = dty * (Math.abs(truedecdate) % 1);
+  if (ispositive) targetday = Math.ceil(targetday);
+  else targetday = dty - Math.floor(targetday);
+
+  // count up days months at a time, until we reach our target month
+  // then the remainder (days) is the day of that month
+  let monthint;
+  let dayspassed = 0;
+  for (let m = 1; m <= 12; m++) {
+    monthint = m;
+    const dtm = decimaldate.daysinmonth(yearint, monthint);
+    if (dayspassed + dtm < targetday) {
+      dayspassed += dtm;
+    } else {
+      break;
     }
-    const dayint = targetday - dayspassed;
-
-    // make string output
-    // months and day as 2 digits
-    // ISO 8601 shift year<=0 by 1, 0=1BCE, -1=2BCE
-    const monthstring = monthint.toString().padStart(2, '0');
-    const daystring = dayint.toString().padStart(2, '0');
-    let yearstring;
-    if (yearint > 0) yearstring = yearint.toString().padStart(4, '0');  // just the year as 4 digits
-    else if (yearint == -1) yearstring = (Math.abs(yearint + 1).toString().padStart(4, '0'));  // BCE offset by 1 but do not add a - sign
-    else yearstring = '-' + (Math.abs(yearint + 1).toString().padStart(4, '0'));  // BCE offset by 1 and add  - sign
-
-    return `${yearstring}-${monthstring}-${daystring}`;
+  }
+  const dayint = targetday - dayspassed;
+
+  // make string output
+  // months and day as 2 digits
+  // ISO 8601 shift year<=0 by 1, 0=1BCE, -1=2BCE
+  const monthstring = monthint.toString().padStart(2, "0");
+  const daystring = dayint.toString().padStart(2, "0");
+  let yearstring;
+  if (yearint > 0) {
+    yearstring = yearint.toString().padStart(4, "0");
+  } // just the year as 4 digits
+  else if (yearint === -1) {
+    yearstring = Math.abs(yearint + 1)
+      .toString()
+      .padStart(4, "0");
+  } // BCE offset by 1 but do not add a - sign
+  else {
+    yearstring =
+      "-" +
+      Math.abs(yearint + 1)
+        .toString()
+        .padStart(4, "0");
+  } // BCE offset by 1 and add  - sign
+
+  return `${yearstring}-${monthstring}-${daystring}`;
 };
 
-
 decimaldate.isvalidmonthday = (yearint, monthint, dayint) => {
-    if (yearint != parseInt(yearint) || yearint == 0) return false;
-    if (monthint != parseInt(monthint)) return false;
-    if (dayint != parseInt(dayint)) return false;
+  if (yearint !== parseInt(yearint, 10) || yearint === 0) return false;
+  if (monthint !== parseInt(monthint, 10)) return false;
+  if (dayint !== parseInt(dayint, 10)) return false;
 
-    if (monthint < 1 || monthint > 12) return false;
-    if (dayint < 1) return false;
+  if (monthint < 1 || monthint > 12) return false;
+  if (dayint < 1) return false;
 
-    const dtm = decimaldate.daysinmonth(yearint, monthint);
-    if (! dtm) return false;
-    if (dayint > dtm) return false;
+  const dtm = decimaldate.daysinmonth(yearint, monthint);
+  if (!dtm) return false;
+  if (dayint > dtm) return false;
 
-    return true;
+  return true;
 };
 
-
 decimaldate.proportionofdayspassed = (yearint, monthint, dayint) => {
-    // count the number of days to get through the prior months
-    let dayspassed = 0;
-    for (let m = 1; m < monthint; m++) {
-        const dtm = decimaldate.daysinmonth(yearint, m);
-        dayspassed += dtm;
-    }
-
-    // add the leftover days not in a prior month
-    // but minus 0.5 to get us to noon of the target day, as opposed to the end of the day
-    dayspassed = dayspassed + dayint - 0.5;
-
-    // divide by days in year, to get decimal portion
-    // even January 1 is 0.5 days in since we snap to 12 noon
-    const dty = decimaldate.daysinyear(yearint);
-    return dayspassed / dty;
+  // count the number of days to get through the prior months
+  let dayspassed = 0;
+  for (let m = 1; m < monthint; m++) {
+    const dtm = decimaldate.daysinmonth(yearint, m);
+    dayspassed += dtm;
+  }
+
+  // add the leftover days not in a prior month
+  // but minus 0.5 to get us to noon of the target day, as opposed to the end of the day
+  dayspassed = dayspassed + dayint - 0.5;
+
+  // divide by days in year, to get decimal portion
+  // even January 1 is 0.5 days in since we snap to 12 noon
+  const dty = decimaldate.daysinyear(yearint);
+  return dayspassed / dty;
 };
 
-
 decimaldate.daysinmonth = (yearint, monthint) => {
-    const monthdaycounts = {
-        1: 31,
-        2: 28,  // February
-        3: 31,
-        4: 30,
-        5: 31,
-        6: 30,
-        7: 31,
-        8: 31,
-        9: 30,
-        10: 31,
-        11: 30,
-        12: 31,
-    };
-
-    if (decimaldate.isleapyear(yearint)) monthdaycounts[2] = 29;
-
-    return monthdaycounts[monthint];
+  const monthdaycounts = {
+    1: 31,
+    2: 28, // February
+    3: 31,
+    4: 30,
+    5: 31,
+    6: 30,
+    7: 31,
+    8: 31,
+    9: 30,
+    10: 31,
+    11: 30,
+    12: 31,
+  };
+
+  if (decimaldate.isleapyear(yearint)) monthdaycounts[2] = 29;
+
+  return monthdaycounts[monthint];
 };
 
-
 decimaldate.daysinyear = (yearint) => {
-    return decimaldate.isleapyear(yearint) ? 366 : 365;
+  return decimaldate.isleapyear(yearint) ? 366 : 365;
 };
 
-
 decimaldate.isleapyear = (yearint) => {
-    if (yearint != parseInt(yearint) || yearint == 0) throw new Error(`isleapyear() invalid year ${yearint}`);
+  if (yearint !== parseInt(yearint, 10) || yearint === 0) {
+    throw new Error(`isleapyear() invalid year ${yearint}`);
+  }
 
-    // don't forget BCE; there is no 0 so leap years are -1, -5, -9, ..., -2001, -2005, ...
-    // just add 1 to the year to correct for this, for this purpose
-    const yearnumber = yearint > 0 ? yearint : yearint + 1;
+  // don't forget BCE; there is no 0 so leap years are -1, -5, -9, ..., -2001, -2005, ...
+  // just add 1 to the year to correct for this, for this purpose
+  const yearnumber = yearint > 0 ? yearint : yearint + 1;
 
-    const isleap = yearnumber % 4 == 0 && (yearnumber % 100 != 0 || yearnumber % 400 == 0);
-    return isleap;
+  const isleap =
+    yearnumber % 4 === 0 && (yearnumber % 100 !== 0 || yearnumber % 400 === 0);
+  return isleap;
 };