Fail early if string format is incorrect

[ileasile]

Consider the example like this:

    barsH {
        x(diffScorePercentage) {
            axis.name = "Diff %"
        }
        y(testLabel) {
            axis.name = ""
        }
        fillColor(barColor) {
            scale = categorical("neg" to Color.RED, "pos" to Color.GREEN)
            legend.type = LegendType.None
        }
        tooltips {
            line(diffScorePercentage, format = ".2f")
        }
    }

It's kandy, but lets-plot spec is generated under the hood. When used in Kotlin notebook, it fails on the attempt of rendering tooltips with:

java.lang.IllegalArgumentException: Wrong number of arguments in pattern '.2f' to format '...'. Expected 1 argument instead of 0
at org.jetbrains.letsPlot.commons.formatting.string.StringFormat$Companion.create$commons(StringFormat.kt:163)
at org.jetbrains.letsPlot.commons.formatting.string.StringFormat$Companion.forOneArg(StringFormat.kt:133)
at org.jetbrains.letsPlot.commons.formatting.string.StringFormat$Companion.forOneArg$default(StringFormat.kt:127)
at org.jetbrains.letsPlot.core.plot.builder.tooltip.data.DataFrameField.initFormatter(DataFrameField.kt:30)
at org.jetbrains.letsPlot.core.plot.builder.tooltip.data.DataFrameField.getDataPoint(DataFrameField.kt:47)
at org.jetbrains.letsPlot.core.plot.builder.tooltip.LinePattern.getDataPoint(LinePattern.kt:41)
at org.jetbrains.letsPlot.core.plot.base.tooltip.ContextualMapping.getDataPoints(ContextualMapping.kt:22)
at org.jetbrains.letsPlot.core.plot.builder.tooltip.spec.TooltipSpecFactory$Helper.<init>(TooltipSpecFactory.kt:35)
at org.jetbrains.letsPlot.core.plot.builder.tooltip.spec.TooltipSpecFactory.create(TooltipSpecFactory.kt:27)
at org.jetbrains.letsPlot.core.plot.builder.tooltip.TooltipRenderer.createTooltipSpecs(TooltipRenderer.kt:256)
at org.jetbrains.letsPlot.core.plot.builder.tooltip.TooltipRenderer.showTooltips(TooltipRenderer.kt:95)
at org.jetbrains.letsPlot.core.plot.builder.tooltip.TooltipRenderer.access$showTooltips(TooltipRenderer.kt:45)
at org.jetbrains.letsPlot.core.plot.builder.tooltip.TooltipRenderer$6.invoke(TooltipRenderer.kt:77)
at org.jetbrains.letsPlot.core.plot.builder.tooltip.TooltipRenderer$6.invoke(TooltipRenderer.kt:77)
at org.jetbrains.letsPlot.commons.intern.observable.event.EventHandlerExKt$handler$1.onEvent(EventHandlerEx.kt:12)
at org.jetbrains.letsPlot.commons.event.MouseEventPeer$dispatch$1.call(MouseEventPeer.kt:41)
at org.jetbrains.letsPlot.commons.event.MouseEventPeer$dispatch$1.call(MouseEventPeer.kt:39)
at org.jetbrains.letsPlot.commons.intern.observable.event.Listeners.fire(Listeners.kt:72)
at org.jetbrains.letsPlot.commons.event.MouseEventPeer.dispatch(MouseEventPeer.kt:39)
at org.jetbrains.letsPlot.awt.plot.FigureToAwt$Companion$buildSinglePlotComponent$2$mouseMoved$2.invoke(FigureToAwt.kt:185)
at org.jetbrains.letsPlot.awt.plot.FigureToAwt$Companion$buildSinglePlotComponent$2$mouseMoved$2.invoke(FigureToAwt.kt:184)
at com.intellij.kotlin.jupyter.plots.IdeaSwingContextBatik.IDEA_EDT_EXECUTOR$lambda$2$lambda$1(IdeaSwingContextBatik.kt:17)
...

My guess is that it could fail earlier, and the error-containing spec shouldn't be even generated.

What do you think? Can the verification of the format be done at the moment we create the spec?

[ileasile]

Kotlin Notebook issue: https://youtrack.jetbrains.com/issue/KTNB-874/IAE-StringFormatCompanion.createcommons