First commit of "advanced" MCI formatting via theme.hjson entries allowing mini-formatting langauge to apply

Example: {BN!styleFirstLower} in 'text' property

core/predefined_mci.js

@@ -22,6 +22,7 @@ const moment = require('moment');
 const async = require('async');
 
 exports.getPredefinedMCIValue = getPredefinedMCIValue;
+exports.getPredefinedMCIFormatObject = getPredefinedMCIFormatObject;
 exports.init = init;
 
 function init(cb) {
@@ -532,3 +533,21 @@ function getPredefinedMCIValue(client, code, extra) {
         return value;
     }
 }
+
+function getPredefinedMCIFormatObject(client, text) {
+    const re = /\{([A-Z]{2})(?:[!:][^}]+)?\}/g;
+    let m;
+    const formatObj = {};
+    while ((m = re.exec(text))) {
+        const v = getPredefinedMCIValue(client, m[1]);
+        if (v) {
+            if (!isNaN(v)) {
+                formatObj[m[1]] = parseInt(v);
+            } else {
+                formatObj[m[1]] = v;
+            }
+        }
+    }
+
+    return _.isEmpty(formatObj) ? null : formatObj;
+}

core/text_view.js

@@ -11,6 +11,9 @@ const renderSubstr = require('./string_util.js').renderSubstr;
 const renderStringLength = require('./string_util.js').renderStringLength;
 const pipeToAnsi = require('./color_codes.js').pipeToAnsi;
 const stripAllLineFeeds = require('./string_util.js').stripAllLineFeeds;
+const getPredefinedMCIFormatObject =
+    require('./predefined_mci').getPredefinedMCIFormatObject;
+const stringFormat = require('./string_format');
 
 //  deps
 const util = require('util');
@@ -153,6 +156,12 @@ TextView.prototype.setText = function (text, redraw) {
         text = text.toString();
     }
 
+    const formatObj = getPredefinedMCIFormatObject(this.client, text);
+    if (formatObj) {
+        // expand before converting
+        text = stringFormat(text, formatObj);
+    }
+
     this.text = pipeToAnsi(stripAllLineFeeds(text), this.client); //  expand MCI/etc.
     if (this.maxLength > 0) {
         this.text = renderSubstr(this.text, 0, this.maxLength);