From a63f1dc0273a834647b79614805c45034cdf795c Mon Sep 17 00:00:00 2001
From: wlandau <will.landau@gmail.com>
Date: Thu, 8 Nov 2018 21:11:09 -0500
Subject: [PATCH] Stop memoization from reacting to spurious changes

to function internals. Related: #345
---
 DESCRIPTION                 |  2 +-
 NEWS.md                     |  2 ++
 R/create_drake_ordinances.R | 38 ++++++++++++++++++++++++++-----------
 3 files changed, 30 insertions(+), 12 deletions(-)

diff --git a/DESCRIPTION b/DESCRIPTION
index ce0163f13..5040b725c 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -108,4 +108,4 @@ VignetteBuilder: knitr
 Encoding: UTF-8
 Language: en-US
 Roxygen: list(markdown = TRUE)
-RoxygenNote: 6.1.0
+RoxygenNote: 6.1.1
diff --git a/NEWS.md b/NEWS.md
index 89154e93f..69d8f5bed 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -10,6 +10,8 @@
 
 - **Large speed boost**: reduce repeated calls to `parse()` in `code_dependencies()`.
 - **Large speed boost**: change the default value of `memory_strategy` (previously `pruning_strategy`) to `"speed"` (previously `"lookahead"`).
+- Compute a special data structure in `drake_config()` (`config$ordinances`) just to store the code analysis results. This is an intermediate structure between the workflow plan data frame and the graph. It will help clean up the internals in future development.
+- Improve memoized preprocessing: deparse all the functions in the environment so the memoization does not react so spurious changes in R internals. Related: #345.
 - Remove strict dependencies on packages `evaluate`, `fs`, `future`, `magrittr`, `parallel`, `R.utils`, `stats`, and `stringi`.
 - Deprecate the `force` argument to `make()` and related functions.
 - Change the name of `prune_envir()` to `manage_memory()`.
diff --git a/R/create_drake_ordinances.R b/R/create_drake_ordinances.R
index 3dd6138c8..bdd94d519 100644
--- a/R/create_drake_ordinances.R
+++ b/R/create_drake_ordinances.R
@@ -20,14 +20,15 @@ create_drake_ordinances <- function(
     trigger = parse_trigger(trigger = trigger, envir = envir),
     globals = sort(c(plan$target, ls(envir = envir, all.names = TRUE)))
   )
-  imports <- cdn_prepare_imports(config)
+  imports <- cdo_prepare_imports(config)
+  imports_kernel <- cdo_imports_kernel(config, imports)
   import_ordinances <- memo_expr(
-    cdn_analyze_imports(config, imports),
+    cdo_analyze_imports(config, imports),
     config$cache,
-    imports
+    imports_kernel
   )
   command_ordinances <- memo_expr(
-    cdn_analyze_commands(config),
+    cdo_analyze_commands(config),
     config$cache,
     config$plan,
     config$trigger,
@@ -37,10 +38,10 @@ create_drake_ordinances <- function(
   c(import_ordinances, command_ordinances)
 }
 
-cdn_prepare_imports <- function(config) {
+cdo_prepare_imports <- function(config) {
   console_preprocess(text = "analyze environment", config = config)
   imports <- as.list(config$envir)
-  cdn_unload_conflicts(
+  cdo_unload_conflicts(
     imports = names(imports),
     targets = config$plan$target,
     envir = config$envir,
@@ -50,7 +51,7 @@ cdn_prepare_imports <- function(config) {
   imports[import_names]
 }
 
-cdn_unload_conflicts <- function(imports, targets, envir, verbose) {
+cdo_unload_conflicts <- function(imports, targets, envir, verbose) {
   common <- intersect(imports, targets)
   if (verbose & length(common)) {
     message(
@@ -61,7 +62,22 @@ cdn_unload_conflicts <- function(imports, targets, envir, verbose) {
   remove(list = common, envir = envir)
 }
 
-cdn_analyze_imports <- function(config, imports) {
+cdo_imports_kernel <- function(config, imports) {
+  out <- lightly_parallelize(
+    X = imports,
+    FUN = function(x) {
+      if (is.function(x)) {
+        x <- deparse(x)
+      }
+      x
+    },
+    jobs = config$jobs
+  )
+  names(out) <- names(imports)
+  out[sort(names(out))]
+}
+
+cdo_analyze_imports <- function(config, imports) {
   names <-  names(imports)
   console_many_targets(
     targets = names,
@@ -88,7 +104,7 @@ cdn_analyze_imports <- function(config, imports) {
   out
 }
 
-cdn_analyze_commands <- function(config) {
+cdo_analyze_commands <- function(config) {
   console_many_targets(
     targets = config$plan$target,
     pattern = "analyze",
@@ -115,7 +131,7 @@ cdn_analyze_commands <- function(config) {
   )
   out <- lightly_parallelize(
     X = ordinances,
-    FUN = cdn_prepare_ordinance,
+    FUN = cdo_prepare_ordinance,
     jobs = config$jobs,
     config = config
   )
@@ -123,7 +139,7 @@ cdn_analyze_commands <- function(config) {
   out
 }
 
-cdn_prepare_ordinance <- function(ordinance, config){
+cdo_prepare_ordinance <- function(ordinance, config){
   ordinance$deps_build <- command_dependencies(
     command = ordinance$command,
     exclude = ordinance$target,