Keep symbol-led specs out of the trimmed-prefix path

camdecoster pointed out that folding $/# into the prefix group broke
symbol-led specs: "$f" became "$~f", an invalid spec, and stripping the
symbol before the trim check meant "$1.500000" would come out as "$1.5"
once the tilde got added. Only sign flags (+, -, (, space) belong in the
stripped prefix; symbol-led specs now fall straight through to the
untrimmed return, matching the existing hex/octal/binary "#" cases.

Added test coverage for $f/#f/$s, reworded the draftlog line to
"improperly handling" since it's not strictly a silent drop anymore.

Author: TemRevil

draftlogs/7900_fix.md

@@ -1 +1 @@
-- Fix `hovertemplate`/`texttemplate`/`tickformat`/`hoverformat` silently ignoring d3-format specs that start with a sign flag such as `+.2f` [[#7900](https://github.com/plotly/plotly.js/pull/7900)]
+- Fix `hovertemplate`/`texttemplate`/`tickformat`/`hoverformat` improperly handling d3-format specs that start with a sign flag such as `+.2f` [[#7900](https://github.com/plotly/plotly.js/pull/7900)]

src/lib/index.js

@@ -19,15 +19,16 @@ lib.adjustFormat = function adjustFormat(formatStr) {
     if (/^\d%/.test(formatStr)) return '~%';
     if (/^\ds/.test(formatStr)) return '~s';
 
-    // A d3-format spec may begin with a sign flag (+, -, (, space) and/or a
-    // symbol ($, #). Look past that prefix before deciding whether to trim, and
-    // reattach it: prepending the tilde to the whole string (e.g. "~+.2f") is an
-    // invalid spec that d3Format rejects, so "+.2f" used to be silently dropped.
-    var prefix = (formatStr.match(/^[+\-( ]?[$#]?/) || [''])[0];
+    // A d3-format spec may begin with a sign flag (+, -, (, space). Look past
+    // that prefix before deciding whether to trim, and reattach it: prepending
+    // the tilde to the whole string (e.g. "~+.2f") is an invalid spec that
+    // d3Format rejects, so "+.2f" used to be silently dropped.
+    var prefix = (formatStr.match(/^[+\-( ]/) || [''])[0];
     var rest = formatStr.slice(prefix.length);
 
-    // try adding tilde to trim trailing zeros
-    if (!/^[~,.0$]/.test(rest) && /[&fps]/.test(rest)) return prefix + '~' + rest;
+    // try adding tilde to trim trailing zeros; leave symbol-led specs ($, #)
+    // untrimmed, since the symbol isn't part of the prefix we stripped above
+    if (!/^[~,.0$#]/.test(rest) && /[&fps]/.test(rest)) return prefix + '~' + rest;
 
     return formatStr;
 };

test/jasmine/tests/lib_number_format_test.js

@@ -59,6 +59,11 @@ describe('number format', function() {
         { format: '+.0f', number: float, exp: '+12346'},
         { format: '-.4f', number: float, exp: '12345.6789'},
 
+        // symbol-led specs ($, #) are left untrimmed
+        { format: '$f', number: 1.5, exp: '$1.500000'},
+        { format: '#f', number: 1.5, exp: '1.500000'},
+        { format: '$s', number: 1500, exp: '$1.50000k'},
+
         // space-filled and default sign
         { format: '-13', number: float, exp: '-12345.678901'},
         { format: '-14', number: float, exp: ' -12345.678901'},