From 7da98b3189c6edd1431acb07954d2a5e95c591a8 Mon Sep 17 00:00:00 2001
From: Justin Yap <justin.yap@displayr.com>
Date: Mon, 13 Jul 2026 15:16:24 +1000
Subject: [PATCH] RS-22593: Expose Price Sensitivity Meter chart title as
 ChartLabels$ChartTitle

The chart title is forwarded to Line via ... but was not exposed on the
output, so consumers reading attr(x, "ChartLabels")$ChartTitle (e.g. the
LLM-readable generation) could not label the chart's data. Merge the title
into the ChartLabels attribute alongside the existing ChartData, without
overwriting the SeriesLabels that Line already sets.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---
 R/pricesensitivitymeter.R                   | 11 +++++++++++
 tests/testthat/test-pricesensitivitymeter.R | 12 ++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/R/pricesensitivitymeter.R b/R/pricesensitivitymeter.R
index 365d8d2..6adf1de 100644
--- a/R/pricesensitivitymeter.R
+++ b/R/pricesensitivitymeter.R
@@ -367,6 +367,17 @@ PriceSensitivityMeter <- function(x,
                             edits = list(annotationPosition = FALSE, annotationText = FALSE,
                                          axisTitleText = FALSE, titleText = FALSE, legendText = FALSE))
     attr(pp, "ChartData") <- psm.dat
+    # Expose the chart title (forwarded to Line via ...) as a ChartLabels$ChartTitle
+    # attribute so downstream consumers can label the chart's data. Merge into any
+    # ChartLabels already set by Line rather than overwriting it.
+    chart.title <- list(...)[["title"]]
+    if (!is.null(chart.title) && any(nzchar(chart.title))) {
+        chart.labels <- attr(pp, "ChartLabels")
+        if (is.null(chart.labels))
+            chart.labels <- list()
+        chart.labels$ChartTitle <- chart.title
+        attr(pp, "ChartLabels") <- chart.labels
+    }
     return(pp)
 }
 
diff --git a/tests/testthat/test-pricesensitivitymeter.R b/tests/testthat/test-pricesensitivitymeter.R
index b78cd8e..52dbf93 100644
--- a/tests/testthat/test-pricesensitivitymeter.R
+++ b/tests/testthat/test-pricesensitivitymeter.R
@@ -231,3 +231,15 @@ test_that("PSM with two axes",
             y2.title.font.family = "Courier New", y2.title.font.color = "#0000FF",
             y2.bounds.minimum = 0.5, y2.bounds.maximum = 5, y2.title = "R"), NA)
 })
+
+test_that("Chart title exposed as ChartLabels$ChartTitle",
+{
+    psm <- PriceSensitivityMeter(dat, title = "My price sensitivity meter")
+    expect_equal(attr(psm, "ChartLabels")$ChartTitle, "My price sensitivity meter")
+    # ChartData is still attached alongside the title
+    expect_false(is.null(attr(psm, "ChartData")))
+
+    # No ChartTitle is exposed when the title is empty
+    psm.no.title <- PriceSensitivityMeter(dat)
+    expect_null(attr(psm.no.title, "ChartLabels")$ChartTitle)
+})