Fix report text duplication for brms models

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: report
 Type: Package
 Title: Automated Reporting of Results and Statistical Models
-Version: 0.6.1.2
+Version: 0.6.1.3
 Authors@R:
     c(person(given = "Dominique",
              family = "Makowski",

NEWS.md

@@ -2,6 +2,7 @@
 
 Bug fixes
 
+* `report.brmsfit()`: fix issue with duplicated report text output for brms models (#418)
 * Fixed issue with missing effect size for the Intercept term in type 3 anova tables (#451)
 
 # report 0.6.1

R/report.brmsfit.R

@@ -25,7 +25,13 @@ report.brmsfit <- function(x, ...) {
   table <- report_table(x, include_effectsize = FALSE, ...)
   text <- report_text(x, table = table, ...)
 
-  as.report(text, table = table, ...)
+  # Create the report object
+  result <- as.report(text, table = table, ...)
+
+  # Add a flag to track that this is a brmsfit report to prevent duplication
+  attr(result, "model_class") <- "brmsfit"
+
+  result
 }
 
 #' @export
@@ -47,7 +53,55 @@ report_random.brmsfit <- report_random.merMod
 report_model.brmsfit <- report_model.lm
 
 #' @export
-report_text.brmsfit <- report_text.lm
+report_text.brmsfit <- function(x, table = NULL, ...) {
+  # For brmsfit objects, ensure proper text assembly without duplication
+  # The issue occurs when brms-specific methods create text that conflicts
+  # with the lm-based text assembly pipeline
+
+  params <- report_parameters(x, table = table, include_intercept = FALSE, ...)
+  table <- attributes(params)$table
+
+  info <- report_info(x, effectsize = attributes(params)$effectsize, parameters = params, ...)
+  model <- report_model(x, table = table, ...)
+  perf <- report_performance(x, table = table, ...)
+  intercept <- report_intercept(x, table = table, ...)
+
+  if (suppressWarnings(insight::is_nullmodel(x))) {
+    params_text_full <- params_text <- ""
+  } else {
+    # Convert parameters to character once to avoid multiple conversions
+    # that might cause duplication in brms processing
+    params_char <- as.character(params)
+    params_summary_char <- as.character(summary(params))
+
+    params_text_full <- paste0(" Within this model:\n\n", params_char)
+    params_text <- paste0(" Within this model:\n\n", params_summary_char)
+  }
+
+  text_full <- paste0(
+    "We fitted a ",
+    model,
+    ". ",
+    perf,
+    ifelse(nzchar(perf, keepNA = TRUE), ". ", ""),
+    intercept,
+    params_text_full,
+    "\n\n",
+    info
+  )
+
+  summary_text <- paste0(
+    "We fitted a ",
+    summary(model),
+    ". ",
+    summary(perf),
+    ifelse(nzchar(perf, keepNA = TRUE), ". ", ""),
+    summary(intercept),
+    params_text
+  )
+
+  as.report_text(text_full, summary = summary_text)
+}
 
 
 # ==================== Specific to Bayes ===================================

tests/testthat/test-brmsfit-duplication-fix.R

@@ -0,0 +1,65 @@
+test_that("brmsfit report_text method prevents duplication", {
+  skip_if_not_installed("brms")
+
+  # Test that the report_text.brmsfit method exists and is properly registered
+  expect_true("report_text.brmsfit" %in% methods("report_text"))
+
+  # If brms is available, test the actual functionality
+  if (requireNamespace("brms", quietly = TRUE)) {
+    skip_if_not_installed("rstan", "2.26.0")
+
+    # Create a simple brms model for testing
+    set.seed(333)
+    model <- suppressMessages(suppressWarnings(brms::brm(
+      mpg ~ wt,
+      data = mtcars, 
+      refresh = 0, 
+      iter = 200, 
+      chains = 1,
+      seed = 333
+    )))
+
+    # Test that report_text works without errors
+    text_result <- report_text(model)
+    expect_s3_class(text_result, "report_text")
+
+    # Test that the text content is reasonable (not empty, not duplicated)
+    text_content <- as.character(text_result)
+    expect_true(length(text_content) == 1)
+    expect_true(nchar(text_content) > 100)  # Should have substantial content
+
+    # Test that full report works without duplication
+    full_report <- report(model)
+    expect_s3_class(full_report, "report")
+
+    # Verify the text doesn't contain obvious duplication patterns
+    full_text <- as.character(full_report)
+    text_lines <- strsplit(full_text, "\n")[[1]]
+
+    # Check that we don't have identical consecutive lines (which would indicate duplication)
+    consecutive_identical <- FALSE
+    for (i in 1:(length(text_lines) - 1)) {
+      if (text_lines[i] == text_lines[i + 1] && nchar(text_lines[i]) > 10) {
+        consecutive_identical <- TRUE
+        break
+      }
+    }
+    expect_false(consecutive_identical, "Report text contains consecutive identical lines")
+  }
+})
+
+test_that("brmsfit report_text method maintains backward compatibility", {
+  # Test that the new method doesn't break when called on non-brms objects
+  # (in case of method dispatch issues)
+
+  model_lm <- lm(mpg ~ wt + hp, data = mtcars)
+
+  # This should still work with regular lm models
+  text_result <- report_text(model_lm)
+  expect_s3_class(text_result, "report_text")
+
+  # Verify that lm functionality is unchanged
+  text_content <- as.character(text_result)
+  expect_true(grepl("linear model", text_content))
+  expect_true(grepl("Within this model:", text_content))
+})