Issue587

CLAUDE.md

@@ -143,8 +143,11 @@ Non-snapshot tests (logical assertions, error checks, etc.) run fine on any plat
 This is a known quirk — don't worry about these specific persistent failures. However, if you see more than ~3 snapshot failures, something real is likely broken and needs investigation.
 
 ### Running Tests
+
+The canonical test workflow is to open the devcontainer and run `make testall`. Do not attempt to run the full test suite outside the devcontainer — snapshot tests will fail due to font/rendering differences, and even non-snapshot tests may pull in snapshot comparisons.
+
 ```bash
-# Via Makefile
+# Via Makefile (inside devcontainer)
 make testall                                          # Run all tests
 make testone testfile="inst/tinytest/test-legend.R"   # Run single test file
 

R/tinyplot.R

@@ -995,6 +995,7 @@ tinyplot.default = function(
       .bp = environment(.h)[["base_par"]]
       if (is.list(.bp)) .tpars = modifyList(.tpars, .bp)
     }
+    if (!is.null(.tpars[["mar"]])) .theme_mar = .tpars[["mar"]]
 
     # Detect outer-legend sides (order: bottom, left, top, right).
     .lgnd_pos = settings$legend_args[["x"]]

inst/tinytest/test-tinytheme.R

@@ -178,3 +178,12 @@ f = function() {
   plt_add(type = "b")
 }
 expect_snapshot_plot(f, label = "ephemeral_default_theme_add")
+
+# User mar override respected under dynmar (#587)
+f = function() {
+  tinytheme("dynamic", mar = c(5, 5, 5, 5))
+  plt(0:10, main = "Custom mar override")
+  box("inner", lty = 2)
+  tinytheme()
+}
+expect_snapshot_plot(f, label = "tinytheme_dynmar_mar_override")