message: display an equation number only for ref token.
diff: @@ -68,7 +68,7 @@ export class HoverProvider implements vscode.HoverProvider {
  if (tex) {
  const newCommand = this.findNewCommand(document.getText())
  tex.texString = newCommand + tex.texString
  - this.provideHoverOnRef(tex)
  + this.provideHoverOnRef(tex, token)
  .then(hover => resolve(hover))
  return
  }
  @@ -121,7 +121,7 @@ export class HoverProvider implements vscode.HoverProvider {
  return new vscode.Hover(new vscode.MarkdownString( `![equation](${md})`), tex.range )
  }
  - private async provideHoverOnRef(tex: TexMathEnv) : Promise<vscode.Hover> {
  + private async provideHoverOnRef(tex: TexMathEnv, refToken: string) : Promise<vscode.Hover> {
  const configuration = vscode.workspace.getConfiguration('latex-workshop')
  const scale = configuration.get('hoverPreview.scale') as number
  const s = this.mathjaxify(tex.texString, tex.envname, {stripLabel: false})
  @@ -137,15 +137,15 @@ export class HoverProvider implements vscode.HoverProvider {
  this.scaleSVG(data, scale)
  this.colorSVG(data)
  const xml = data.svgNode.outerHTML
  - const eqNumAndLabels = this.eqNumAndLabels(obj, tex)
  + const eqNumAndLabels = this.eqNumAndLabel(obj, tex, refToken)
  const md = this.svgToDataUrl(xml)
  return new vscode.Hover(new vscode.MarkdownString( eqNumAndLabels + `![equation](${md})`), tex.range )
  }
  - private eqNumAndLabels(obj: LabelsStore, tex: TexMathEnv) : string {
  + private eqNumAndLabel(obj: LabelsStore, tex: TexMathEnv, refToken: string) : string {
  let s = ''
  const horizontalLine = '\n- - -\n\n'
  - const e = "cannot get a label for each number" + horizontalLine
  + const e = "[error] fail to get equation number for label." + horizontalLine
  const labels = tex.texString.match(/\\label\{.*?\}/g)
  if (!labels) {
  return e
  @@ -157,25 +157,25 @@ export class HoverProvider implements vscode.HoverProvider {
  let i = 1
  for(const label0 of labels) {
  const label = label0.substr(7, label0.length - 8)
  - s += `(${i}) ${label}` + '&nbsp;&nbsp;&nbsp;'
  + if (refToken === label) {
  + s = `(${i}) ${label}` + '&nbsp;&nbsp;&nbsp;'
  + return s + horizontalLine
  + }
  i += 1
  }
  - s += horizontalLine
  - return s
  + return e
  }
  - const ret0 : [number, string][] = []
  for(const label in obj.labels) {
  const labelNum = obj.labels[label].tag
  if (!labelNum.match(/\d+/)) {
  return e
  }
  - ret0.push([Number(labelNum), label])
  + if (refToken === label) {
  + s = `(${labelNum}) ${label}` + '&nbsp;&nbsp;&nbsp;'
  + return s + horizontalLine
  }
  - const ret = ret0.sort( (a, b) => a[0] - b[0] )
  - for(const item of ret) {
  - s += `(${item[0]}) ${item[1]}` + '&nbsp;&nbsp;&nbsp;'
  }
  - return s + horizontalLine
  + return e
  }
  private scaleSVG(data: any, scale: number) {
  