[elpa] externals/parser-generator daf93e0 097/434: Added failing unit test for action tables generation

[ELPA Syncer]

branch: externals/parser-generator
commit daf93e05932bdcf07cd57da45f919b274cc06881
Author: Christian Johansson <christian@cvj.se>
Commit: Christian Johansson <christian@cvj.se>

    Added failing unit test for action tables generation
---
 parser-lr.el           | 31 ++++++++++++++++++++++---------
 test/parser-lr-test.el | 29 ++++++++++++++++++++++++++++-
 2 files changed, 50 insertions(+), 10 deletions(-)

diff --git a/parser-lr.el b/parser-lr.el
index 0aa54d4..25799ad 100644
--- a/parser-lr.el
+++ b/parser-lr.el
@@ -25,7 +25,7 @@
   "Hash-table for distinct LR-items in grammar.")
 
 
-;; Functions
+;; Helper Functions
 
 
 (defun parser-lr--reset ()
@@ -37,6 +37,26 @@
 
 ;; Main Algorithms
 
+
+;; Algorithm 5.11, p. 393
+(defun parser-lr--generate-action-tables ()
+  "Generate action-tables for lr-grammar."
+  (unless parser-lr--action-tables
+    (let ((action-tables nil)
+          (terminals (parser--get-grammar-terminals)))
+      (dolist (goto-table parser-lr--goto-tables)
+        ;; (message "goto-table: %s" goto-table)
+        (let ((goto-index (car goto-table))
+              (gotos (car (cdr goto-table))))
+          (let ((lr-items (gethash goto-index parser-lr--items)))
+            (dolist (lr-item lr-items)
+              ;; TODO (a) f(u) = shift if [A -> B . C, v] is in a, C != e and 
u is in EFF(Cv)
+              ;; TODO (b) f(u) = reduce i if [A -> B ., u] is in a and A -> B 
is product i in P, i > 1
+              ;; TODO (c) f(e) = accept if [S' -> S ., e] is in a
+              ;; TODO (d) f(u) = error otherwise
+              ))))
+      (setq parser-lr--action-table action-tables))))
+
 ;; Algorithm 5.9, p. 389
 (defun parser-lr--generate-goto-tables ()
   "Calculate set of valid LR(k) items for grammar and a GOTO-table."
@@ -117,8 +137,7 @@
     (unless
         (parser-lr--items-valid-p
          (parser--hash-values-to-list parser-lr--items t))
-      (error "Inconsistent grammar!")))
-  t)
+      (error "Inconsistent grammar!"))))
 
 ;; Algorithm 5.10, p. 391
 (defun parser-lr--items-valid-p (lr-item-sets)
@@ -370,12 +389,6 @@
     (setq lr-new-item (sort lr-new-item 'parser--sort-list))
     lr-new-item))
 
-;; Algorithm 5.11, p. 393
-(defun parser-lr--generate-action-tables ()
-  "Generate action-tables for lr-grammar."
-  ;; TODO This
-  t)
-
 
 (provide 'parser-lr)
 
diff --git a/test/parser-lr-test.el b/test/parser-lr-test.el
index 8988a3b..d57acd1 100644
--- a/test/parser-lr-test.el
+++ b/test/parser-lr-test.el
@@ -9,6 +9,32 @@
 (require 'parser-lr)
 (require 'ert)
 
+(defun parser-lr-test--generate-action-tables ()
+  "Test `parser-lr--generate-action-tables'."
+  (message "Starting tests for (parser-lr--generate-action-tables)")
+
+  ;; Example 5.32 p. 393
+  (parser-lr--reset)
+  (parser--set-grammar '((Sp S) (a b) ((Sp S) (S (S a S b)) (S e)) Sp))
+  (parser--set-look-ahead-number 1)
+  (parser-lr--generate-goto-tables)
+  (parser-lr--generate-action-tables)
+
+  ;; Fig. 5.9 p. 374
+  (should
+   (equal
+    '((0 ((a reduce 2) (e reduce 2)))
+      (1 ((a shift) (e accept)))
+      (2 ((a reduce 2) (b reduce 2)))
+      (3 ((a shift) (b shift)))
+      (4 ((a reduce 2) (b reduce 2)))
+      (5 ((a reduce 1) (e reduce 1)))
+      (6 ((a shift) (b shift)))
+      (7 ((a reduce 1) (b reduce 1))))
+      parser-lr--action-tables))
+
+  (message "Ended tests for (parser-lr--generate-action-tables)"))
+
 (defun parser-lr-test--generate-goto-tables ()
   "Test `parser-lr--generate-goto-tables'."
   (message "Starting tests for (parser-lr--generate-goto-tables)")
@@ -165,8 +191,9 @@
   ;; (setq debug-on-error t)
 
   (parser-lr-test--items-for-prefix)
+  (parser-lr-test--items-valid-p)
   (parser-lr-test--generate-goto-tables)
-  (parser-lr-test--items-valid-p))
+  (parser-lr-test--generate-action-tables))
 
 (provide 'parser-lr-test)