template-parser: renderer: implemented 'else' support in templates

yeah, this is stupid. after more than 320 commits and 26 releases, we
finally support the 'else' statement in the template engine. I don't
know if I'm dumb or what, but it took me that long to find a "simple"
solution to this basic issue. yep, no more
`{% ifdef FOO %}...{% endif %}{% ifndef FOO %}...{% endif %}` blocks.
but seriously, who cares?! :/

7 files changed, 421 insertions, 16 deletions

diff --git a/man/blogc-template.7.ronn b/man/blogc-template.7.ronn
index 3499d7c..1fdc479 100644
--- a/man/blogc-template.7.ronn
+++ b/man/blogc-template.7.ronn
@@ -143,7 +143,8 @@ based on the value and existence of variables in the current scope.
 The implementation of conditionals is simple, and each will just evaluate the
 value of a single variable.
 
-The available conditionals are: `ifdef`, `ifndef` and `if`.
+The available conditionals are: `ifdef`, `ifndef` and `if`. `else` statements
+are supported.
 
 ### ifdef conditional
 
@@ -154,9 +155,12 @@ This is how an `ifdef` conditional is defined in a template:
 
     {% ifdef TITLE %}
     This is title: {{ TITLE }}
+    {% else %}
+    Untitled entry
     {% endif %}
 
-In this case, if the `TITLE` variable is defined, the content is included.
+In this case, if the `TITLE` variable is defined, the content after the statement
+is included. Otherwise, the content after `else` statement is included.
 
 ### ifndef conditional
 
@@ -170,6 +174,8 @@ This is how an `ifndef` conditional is defined in a template:
     {% endif %}
 
 In this case, if the `TITLE` variable is not defined, the content is included.
+`else` statements are supported here, even if it does not makes much sense to
+be used this way.
 
 ### if conditional
 
@@ -184,7 +190,9 @@ comparisions are strcmp(3)-like.
 This is how an `if` conditional is defined in a template:
 
     {% if TITLE == "My Title" %}
-    Title is "My Title"
+    Special description of "My Title"
+    {% else %}
+    Title is {{ TITLE }}
     {% endif %}
 
 Or:
diff --git a/src/debug.c b/src/debug.c
index 767e1a5..7039608 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -55,6 +55,9 @@ blogc_debug_template(sb_slist_t *stmts)
                 fprintf(stderr, "IF: %s %s %s", data->value,
                     get_operator(data->op), data->value2);
                 break;
+            case BLOGC_TEMPLATE_ELSE_STMT:
+                fprintf(stderr, "ELSE");
+                break;
             case BLOGC_TEMPLATE_ENDIF_STMT:
                 fprintf(stderr, "ENDIF");
                 break;
diff --git a/src/renderer.c b/src/renderer.c
index 0f71ba7..351dfb1 100644
--- a/src/renderer.c
+++ b/src/renderer.c
@@ -188,6 +188,7 @@ blogc_render(sb_slist_t *tmpl, sb_slist_t *sources, sb_trie_t *config, bool list
     bool if_not = false;
     bool inside_block = false;
     bool evaluate = false;
+    bool valid_else = false;
 
     int cmp = 0;
 
@@ -343,13 +344,23 @@ blogc_render(sb_slist_t *tmpl, sb_slist_t *sources, sb_trie_t *config, bool list
                             if_count++;
                             continue;
                         }
+                        if ((stmt->type == BLOGC_TEMPLATE_ELSE_STMT) &&
+                            (if_count == 0))
+                        {
+                            // this is somewhat complex. only an else statement
+                            // right after a non evaluated block should be considered
+                            // valid, because all the inner conditionals were just
+                            // skipped, and all the outter conditionals evaluated
+                            // to true.
+                            valid_else = true;
+                            break;
+                        }
                         if (stmt->type == BLOGC_TEMPLATE_ENDIF_STMT) {
                             if (if_count > 0) {
                                 if_count--;
                                 continue;
                             }
-                            if (if_count == 0)
-                                break;
+                            break;
                         }
                     }
                 }
@@ -358,7 +369,41 @@ blogc_render(sb_slist_t *tmpl, sb_slist_t *sources, sb_trie_t *config, bool list
                 if_not = false;
                 break;
 
+            case BLOGC_TEMPLATE_ELSE_STMT:
+                if_count = 0;
+                if (!valid_else) {
+
+                    // at this point we can just skip anything, counting the
+                    // number of 'if's, to know how many 'endif's we need to
+                    // skip as well.
+                    while (1) {
+                        tmp = tmp->next;
+                        stmt = tmp->data;
+                        if ((stmt->type == BLOGC_TEMPLATE_IF_STMT) ||
+                            (stmt->type == BLOGC_TEMPLATE_IFDEF_STMT) ||
+                            (stmt->type == BLOGC_TEMPLATE_IFNDEF_STMT))
+                        {
+                            if_count++;
+                            continue;
+                        }
+                        // no need to handle else statements here, because every
+                        // if should have an endif.
+                        if (stmt->type == BLOGC_TEMPLATE_ENDIF_STMT) {
+                            if (if_count > 0) {
+                                if_count--;
+                                continue;
+                            }
+                            break;
+                        }
+                    }
+                }
+                valid_else = false;
+                break;
+
             case BLOGC_TEMPLATE_ENDIF_STMT:
+                // any endif statement should invalidate valid_else, to avoid
+                // propagation to outter conditionals.
+                valid_else = false;
                 if (if_count > 0)
                     if_count--;
                 break;
diff --git a/src/template-parser.c b/src/template-parser.c
index 525f5f5..344e398 100644
--- a/src/template-parser.c
+++ b/src/template-parser.c
@@ -69,6 +69,7 @@ blogc_template_parse(const char *src, size_t src_len, blogc_error_t **err)
     blogc_template_stmt_operator_t tmp_op = 0;
 
     unsigned int if_count = 0;
+    bool else_open = false;
     bool foreach_open = false;
 
     sb_slist_t *stmts = NULL;
@@ -224,6 +225,7 @@ blogc_template_parse(const char *src, size_t src_len, blogc_error_t **err)
                         type = BLOGC_TEMPLATE_IFDEF_STMT;
                         start = current;
                         if_count++;
+                        else_open = false;
                         break;
                     }
                     else if ((current - start == 6) &&
@@ -233,6 +235,7 @@ blogc_template_parse(const char *src, size_t src_len, blogc_error_t **err)
                         type = BLOGC_TEMPLATE_IFNDEF_STMT;
                         start = current;
                         if_count++;
+                        else_open = false;
                         break;
                     }
                     else if ((current - start == 2) &&
@@ -242,6 +245,29 @@ blogc_template_parse(const char *src, size_t src_len, blogc_error_t **err)
                         type = BLOGC_TEMPLATE_IF_STMT;
                         start = current;
                         if_count++;
+                        else_open = false;
+                        break;
+                    }
+                    else if ((current - start == 4) &&
+                        (0 == strncmp("else", src + start, 4)))
+                    {
+                        if (if_count > 0) {
+                            if (!else_open) {
+                                state = TEMPLATE_BLOCK_END_WHITESPACE_CLEANER;
+                                type = BLOGC_TEMPLATE_ELSE_STMT;
+                                else_open = true;
+                                break;
+                            }
+                            *err = blogc_error_parser(BLOGC_ERROR_TEMPLATE_PARSER,
+                                src, src_len, current,
+                                "More than one 'else' statement for an open 'if', "
+                                "'ifdef' or 'ifndef' statement.");
+                            break;
+                        }
+                        *err = blogc_error_parser(BLOGC_ERROR_TEMPLATE_PARSER,
+                            src, src_len, current,
+                            "'else' statement without an open 'if', 'ifdef' or "
+                            "'ifndef' statement.");
                         break;
                     }
                     else if ((current - start == 5) &&
@@ -251,12 +277,13 @@ blogc_template_parse(const char *src, size_t src_len, blogc_error_t **err)
                             state = TEMPLATE_BLOCK_END_WHITESPACE_CLEANER;
                             type = BLOGC_TEMPLATE_ENDIF_STMT;
                             if_count--;
+                            else_open = false;
                             break;
                         }
                         *err = blogc_error_parser(BLOGC_ERROR_TEMPLATE_PARSER,
                             src, src_len, current,
-                            "'endif' statement without an open 'ifdef' or 'ifndef' "
-                            "statement.");
+                            "'endif' statement without an open 'if', 'ifdef' or "
+                            "'ifndef' statement.");
                         break;
                     }
                     else if ((current - start == 7) &&
diff --git a/src/template-parser.h b/src/template-parser.h
index 46223ec..fe2721e 100644
--- a/src/template-parser.h
+++ b/src/template-parser.h
@@ -21,6 +21,7 @@ typedef enum {
     BLOGC_TEMPLATE_IFDEF_STMT = 1,
     BLOGC_TEMPLATE_IFNDEF_STMT,
     BLOGC_TEMPLATE_IF_STMT,
+    BLOGC_TEMPLATE_ELSE_STMT,
     BLOGC_TEMPLATE_ENDIF_STMT,
     BLOGC_TEMPLATE_FOREACH_STMT,
     BLOGC_TEMPLATE_ENDFOREACH_STMT,
diff --git a/tests/check_renderer.c b/tests/check_renderer.c
index 0f17d23..cbd4a8e 100644
--- a/tests/check_renderer.c
+++ b/tests/check_renderer.c
@@ -74,7 +74,7 @@ test_render_entry(void **state)
         "{% if GUDA == \"zxc\" %}LOL{% endif %}\n"
         "{% if GUDA != \"bola\" %}HEHE{% endif %}\n"
         "{% if GUDA < \"zxd\" %}LOL2{% endif %}\n"
-        "{% if GUDA > \"zxd\" %}LOL3{% endif %}\n"
+        "{% if GUDA > \"zxd\" %}LOL3{% else %}ELSE{% endif %}\n"
         "{% if GUDA <= \"zxc\" %}LOL4{% endif %}\n"
         "{% foreach TAGS %}lol {{ FOREACH_ITEM }} haha {% endforeach %}\n"
         "{% foreach TAGS_ASD %}yay{% endforeach %}\n";
@@ -99,7 +99,7 @@ test_render_entry(void **state)
         "LOL\n"
         "HEHE\n"
         "LOL2\n"
-        "\n"
+        "ELSE\n"
         "LOL4\n"
         "lol foo haha lol bar haha lol baz haha \n"
         "\n");
@@ -282,6 +282,146 @@ test_render_ifdef3(void **state)
 
 
 static void
+test_render_ifdef4(void **state)
+{
+    const char *str =
+        "{% block entry %}\n"
+        "{% ifdef GUDA %}guda\n"
+        "{% ifdef BOLA %}bola\n"
+        "{% ifdef CHUNDA %}chunda\n"
+        "{% else %}else\n"
+        "{% endif %}\n"
+        "{% endif %}\n"
+        "{% else %}lol\n"
+        "{% endif %}\n"
+        "{% endblock %}\n";
+    blogc_error_t *err = NULL;
+    sb_slist_t *l = blogc_template_parse(str, strlen(str), &err);
+    assert_non_null(l);
+    assert_null(err);
+    sb_slist_t *s = create_sources(1);
+    assert_non_null(s);
+    char *out = blogc_render(l, s, NULL, false);
+    assert_string_equal(out,
+        "\n"
+        "guda\n"
+        "bola\n"
+        "else\n"
+        "\n"
+        "\n"
+        "\n"
+        "\n");
+    blogc_template_free_stmts(l);
+    sb_slist_free_full(s, (sb_free_func_t) sb_trie_free);
+    free(out);
+}
+
+
+static void
+test_render_ifdef5(void **state)
+{
+    const char *str =
+        "{% block entry %}\n"
+        "{% ifdef GUDA %}guda\n"
+        "{% ifdef CHUNDA %}chunda\n"
+        "{% ifdef BOLA %}bola\n"
+        "{% endif %}\n"
+        "{% else %}else\n"
+        "{% endif %}\n"
+        "{% else %}lol\n"
+        "{% endif %}\n"
+        "{% endblock %}\n";
+    blogc_error_t *err = NULL;
+    sb_slist_t *l = blogc_template_parse(str, strlen(str), &err);
+    assert_non_null(l);
+    assert_null(err);
+    sb_slist_t *s = create_sources(1);
+    assert_non_null(s);
+    char *out = blogc_render(l, s, NULL, false);
+    assert_string_equal(out,
+        "\n"
+        "guda\n"
+        "else\n"
+        "\n"
+        "\n"
+        "\n");
+    blogc_template_free_stmts(l);
+    sb_slist_free_full(s, (sb_free_func_t) sb_trie_free);
+    free(out);
+}
+
+
+static void
+test_render_ifdef6(void **state)
+{
+    const char *str =
+        "{% block entry %}\n"
+        "{% ifdef CHUNDA %}chunda\n"
+        "{% ifdef GUDA %}guda\n"
+        "{% ifdef BOLA %}bola\n"
+        "{% endif %}\n"
+        "{% else %}else\n"
+        "{% endif %}\n"
+        "{% else %}lol\n"
+        "{% endif %}\n"
+        "{% endblock %}\n";
+    blogc_error_t *err = NULL;
+    sb_slist_t *l = blogc_template_parse(str, strlen(str), &err);
+    assert_non_null(l);
+    assert_null(err);
+    sb_slist_t *s = create_sources(1);
+    assert_non_null(s);
+    char *out = blogc_render(l, s, NULL, false);
+    assert_string_equal(out,
+        "\n"
+        "lol\n"
+        "\n"
+        "\n");
+    blogc_template_free_stmts(l);
+    sb_slist_free_full(s, (sb_free_func_t) sb_trie_free);
+    free(out);
+}
+
+
+static void
+test_render_ifdef7(void **state)
+{
+    const char *str =
+        "{% block entry %}\n"
+        "{% ifdef GUDA %}guda\n"
+        "{% ifdef BOLA %}bola\n"
+        "{% ifdef CHUNDA %}chunda\n"
+        "{% endif %}\n"
+        "{% endif %}\n"
+        "{% ifdef CHUNDA %}ch\n"
+        "{% else %}else\n"
+        "{% endif %}\n"
+        "{% endif %}\n"
+        "{% endblock %}\n";
+    blogc_error_t *err = NULL;
+    sb_slist_t *l = blogc_template_parse(str, strlen(str), &err);
+    assert_non_null(l);
+    assert_null(err);
+    sb_slist_t *s = create_sources(1);
+    assert_non_null(s);
+    char *out = blogc_render(l, s, NULL, false);
+    assert_string_equal(out,
+        "\n"
+        "guda\n"
+        "bola\n"
+        "\n"
+        "\n"
+        "else\n"
+        "\n"
+        "\n"
+        "\n");
+    blogc_template_free_stmts(l);
+    sb_slist_free_full(s, (sb_free_func_t) sb_trie_free);
+    free(out);
+}
+
+
+static void
 test_render_ifndef(void **state)
 {
     const char *str =
@@ -289,6 +429,7 @@ test_render_ifndef(void **state)
         "{% ifndef CHUNDA %}chunda\n"
         "{% ifdef GUDA %}guda\n"
         "{% ifndef BOLA %}bola\n"
+        "{% else %}else\n"
         "{% endif %}\n"
         "{% endif %}\n"
         "{% endif %}\n"
@@ -304,6 +445,7 @@ test_render_ifndef(void **state)
         "\n"
         "chunda\n"
         "guda\n"
+        "else\n"
         "\n"
         "\n"
         "\n"
@@ -323,6 +465,7 @@ test_render_if_eq(void **state)
         "{% if GUDA == \"zxc\" %}guda\n"
         "{% ifdef BOLA %}bola\n"
         "{% if GUDA > \"zxc\" %}asd\n"
+        "{% else %}else\n"
         "{% endif %}\n"
         "{% endif %}\n"
         "{% endif %}\n"
@@ -339,6 +482,7 @@ test_render_if_eq(void **state)
         "gudabola\n"
         "guda\n"
         "bola\n"
+        "else\n"
         "\n"
         "\n"
         "\n"
@@ -358,6 +502,7 @@ test_render_if_neq(void **state)
         "{% if GUDA != \"zxa\" %}guda\n"
         "{% ifdef BOLA %}bola\n"
         "{% if GUDA > \"zxc\" %}asd\n"
+        "{% else %}else\n"
         "{% endif %}\n"
         "{% endif %}\n"
         "{% endif %}\n"
@@ -374,6 +519,7 @@ test_render_if_neq(void **state)
         "gudabola\n"
         "guda\n"
         "bola\n"
+        "else\n"
         "\n"
         "\n"
         "\n"
@@ -393,6 +539,7 @@ test_render_if_lt(void **state)
         "{% if GUDA < \"zxe\" %}guda\n"
         "{% ifdef BOLA %}bola\n"
         "{% if GUDA > \"zxc\" %}asd\n"
+        "{% else %}else\n"
         "{% endif %}\n"
         "{% endif %}\n"
         "{% endif %}\n"
@@ -409,6 +556,7 @@ test_render_if_lt(void **state)
         "gudabola\n"
         "guda\n"
         "bola\n"
+        "else\n"
         "\n"
         "\n"
         "\n"
@@ -428,6 +576,7 @@ test_render_if_gt(void **state)
         "{% if GUDA > \"zxa\" %}guda\n"
         "{% ifdef BOLA %}bola\n"
         "{% if GUDA > \"zxc\" %}asd\n"
+        "{% else %}else\n"
         "{% endif %}\n"
         "{% endif %}\n"
         "{% endif %}\n"
@@ -444,6 +593,7 @@ test_render_if_gt(void **state)
         "gudabola\n"
         "guda\n"
         "bola\n"
+        "else\n"
         "\n"
         "\n"
         "\n"
@@ -464,6 +614,7 @@ test_render_if_lt_eq(void **state)
         "{% if GUDA <= \"zxe\" %}guda2\n"
         "{% ifdef BOLA %}bola\n"
         "{% if GUDA > \"zxc\" %}asd\n"
+        "{% else %}else\n"
         "{% endif %}\n"
         "{% endif %}\n"
         "{% endif %}\n"
@@ -482,6 +633,7 @@ test_render_if_lt_eq(void **state)
         "guda\n"
         "guda2\n"
         "bola\n"
+        "else\n"
         "\n"
         "\n"
         "\n"
@@ -503,6 +655,7 @@ test_render_if_gt_eq(void **state)
         "{% if GUDA >= \"zxa\" %}guda2\n"
         "{% ifdef BOLA %}bola\n"
         "{% if GUDA > \"zxc\" %}asd\n"
+        "{% else %}else\n"
         "{% endif %}\n"
         "{% endif %}\n"
         "{% endif %}\n"
@@ -521,6 +674,7 @@ test_render_if_gt_eq(void **state)
         "guda\n"
         "guda2\n"
         "bola\n"
+        "else\n"
         "\n"
         "\n"
         "\n"
@@ -582,6 +736,32 @@ test_render_foreach_if(void **state)
 
 
 static void
+test_render_foreach_if_else(void **state)
+{
+    const char *str =
+        "{% block entry %}\n"
+        "{% foreach TAGS %}{% if FOREACH_ITEM == \"bar\" %}yay"
+        "{% else %}{{ FOREACH_ITEM }}"
+        "{% endif %} {% endforeach %}\n"
+        "{% endblock %}\n";
+    blogc_error_t *err = NULL;
+    sb_slist_t *l = blogc_template_parse(str, strlen(str), &err);
+    assert_non_null(l);
+    assert_null(err);
+    sb_slist_t *s = create_sources(1);
+    assert_non_null(s);
+    char *out = blogc_render(l, s, NULL, false);
+    assert_string_equal(out,
+        "\n"
+        "foo yay baz \n"
+        "\n");
+    blogc_template_free_stmts(l);
+    sb_slist_free_full(s, (sb_free_func_t) sb_trie_free);
+    free(out);
+}
+
+
+static void
 test_render_null(void **state)
 {
     assert_null(blogc_render(NULL, NULL, NULL, false));
@@ -943,6 +1123,10 @@ main(void)
         unit_test(test_render_ifdef),
         unit_test(test_render_ifdef2),
         unit_test(test_render_ifdef3),
+        unit_test(test_render_ifdef4),
+        unit_test(test_render_ifdef5),
+        unit_test(test_render_ifdef6),
+        unit_test(test_render_ifdef7),
         unit_test(test_render_ifndef),
         unit_test(test_render_if_eq),
         unit_test(test_render_if_neq),
@@ -952,6 +1136,7 @@ main(void)
         unit_test(test_render_if_gt_eq),
         unit_test(test_render_foreach),
         unit_test(test_render_foreach_if),
+        unit_test(test_render_foreach_if_else),
         unit_test(test_render_null),
         unit_test(test_render_outside_block),
         unit_test(test_render_prefer_local_variable),
diff --git a/tests/check_template_parser.c b/tests/check_template_parser.c
index 40a09be..e94b9c7 100644
--- a/tests/check_template_parser.c
+++ b/tests/check_template_parser.c
@@ -62,7 +62,7 @@ test_template_parse(void **state)
         "{% block listing %}{{ BOLA }}{% endblock %}\n"
         "{% block listing_once %}asd{% endblock %}\n"
         "{%- foreach BOLA %}hahaha{% endforeach %}\n"
-        "{% if BOLA == \"1\\\"0\" %}aee{% endif %}";
+        "{% if BOLA == \"1\\\"0\" %}aee{% else %}fffuuuuuuu{% endif %}";
     blogc_error_t *err = NULL;
     sb_slist_t *stmts = blogc_template_parse(a, strlen(a), &err);
     assert_null(err);
@@ -119,8 +119,12 @@ test_template_parse(void **state)
     blogc_assert_template_stmt(tmp->next->next->next->next->next, "aee",
         BLOGC_TEMPLATE_CONTENT_STMT);
     blogc_assert_template_stmt(tmp->next->next->next->next->next->next, NULL,
-        BLOGC_TEMPLATE_ENDIF_STMT);
-    assert_null(tmp->next->next->next->next->next->next->next);
+        BLOGC_TEMPLATE_ELSE_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next->next->next->next->next,
+        "fffuuuuuuu", BLOGC_TEMPLATE_CONTENT_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next->next->next->next->next->next,
+        NULL, BLOGC_TEMPLATE_ENDIF_STMT);
+    assert_null(tmp->next->next->next->next->next->next->next->next->next);
     blogc_template_free_stmts(stmts);
 }
 
@@ -142,7 +146,7 @@ test_template_parse_crlf(void **state)
         "{% block listing %}{{ BOLA }}{% endblock %}\r\n"
         "{% block listing_once %}asd{% endblock %}\r\n"
         "{%- foreach BOLA %}hahaha{% endforeach %}\r\n"
-        "{% if BOLA == \"1\\\"0\" %}aee{% endif %}";
+        "{% if BOLA == \"1\\\"0\" %}aee{% else %}fffuuuuuuu{% endif %}";
     blogc_error_t *err = NULL;
     sb_slist_t *stmts = blogc_template_parse(a, strlen(a), &err);
     assert_null(err);
@@ -199,8 +203,12 @@ test_template_parse_crlf(void **state)
     blogc_assert_template_stmt(tmp->next->next->next->next->next, "aee",
         BLOGC_TEMPLATE_CONTENT_STMT);
     blogc_assert_template_stmt(tmp->next->next->next->next->next->next, NULL,
-        BLOGC_TEMPLATE_ENDIF_STMT);
-    assert_null(tmp->next->next->next->next->next->next->next);
+        BLOGC_TEMPLATE_ELSE_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next->next->next->next->next,
+        "fffuuuuuuu", BLOGC_TEMPLATE_CONTENT_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next->next->next->next->next->next,
+        NULL, BLOGC_TEMPLATE_ENDIF_STMT);
+    assert_null(tmp->next->next->next->next->next->next->next->next->next);
     blogc_template_free_stmts(stmts);
 }
 
@@ -369,6 +377,74 @@ test_template_parse_ifdef_and_var_outside_block(void **state)
 
 
 static void
+test_template_parse_nested_else(void **state)
+{
+    const char *a =
+        "{% ifdef GUDA %}\n"
+        "{% ifdef BOLA %}\n"
+        "asd\n"
+        "{% else %}\n"
+        "{% ifdef CHUNDA %}\n"
+        "qwe\n"
+        "{% else %}\n"
+        "rty\n"
+        "{% endif %}\n"
+        "{% endif %}\n"
+        "{% ifdef LOL %}\n"
+        "zxc\n"
+        "{% else %}\n"
+        "bnm\n"
+        "{% endif %}\n"
+        "{% endif %}\n";
+    blogc_error_t *err = NULL;
+    sb_slist_t *stmts = blogc_template_parse(a, strlen(a), &err);
+    assert_null(err);
+    assert_non_null(stmts);
+    blogc_assert_template_stmt(stmts, "GUDA", BLOGC_TEMPLATE_IFDEF_STMT);
+    blogc_assert_template_stmt(stmts->next, "\n", BLOGC_TEMPLATE_CONTENT_STMT);
+    blogc_assert_template_stmt(stmts->next->next, "BOLA", BLOGC_TEMPLATE_IFDEF_STMT);
+    blogc_assert_template_stmt(stmts->next->next->next, "\nasd\n",
+        BLOGC_TEMPLATE_CONTENT_STMT);
+    blogc_assert_template_stmt(stmts->next->next->next->next, NULL,
+        BLOGC_TEMPLATE_ELSE_STMT);
+    blogc_assert_template_stmt(stmts->next->next->next->next->next, "\n",
+        BLOGC_TEMPLATE_CONTENT_STMT);
+    blogc_assert_template_stmt(stmts->next->next->next->next->next->next,
+        "CHUNDA", BLOGC_TEMPLATE_IFDEF_STMT);
+    blogc_assert_template_stmt(stmts->next->next->next->next->next->next->next,
+        "\nqwe\n", BLOGC_TEMPLATE_CONTENT_STMT);
+    sb_slist_t *tmp = stmts->next->next->next->next->next->next->next->next;
+    blogc_assert_template_stmt(tmp, NULL, BLOGC_TEMPLATE_ELSE_STMT);
+    blogc_assert_template_stmt(tmp->next, "\nrty\n", BLOGC_TEMPLATE_CONTENT_STMT);
+    blogc_assert_template_stmt(tmp->next->next, NULL,
+        BLOGC_TEMPLATE_ENDIF_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next, "\n",
+        BLOGC_TEMPLATE_CONTENT_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next->next, NULL,
+        BLOGC_TEMPLATE_ENDIF_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next->next->next, "\n",
+        BLOGC_TEMPLATE_CONTENT_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next->next->next->next,
+        "LOL", BLOGC_TEMPLATE_IFDEF_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next->next->next->next->next,
+        "\nzxc\n", BLOGC_TEMPLATE_CONTENT_STMT);
+    tmp = tmp->next->next->next->next->next->next->next->next;
+    blogc_assert_template_stmt(tmp, NULL, BLOGC_TEMPLATE_ELSE_STMT);
+    blogc_assert_template_stmt(tmp->next, "\nbnm\n", BLOGC_TEMPLATE_CONTENT_STMT);
+    blogc_assert_template_stmt(tmp->next->next, NULL,
+        BLOGC_TEMPLATE_ENDIF_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next, "\n",
+        BLOGC_TEMPLATE_CONTENT_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next->next, NULL,
+        BLOGC_TEMPLATE_ENDIF_STMT);
+    blogc_assert_template_stmt(tmp->next->next->next->next->next, "\n",
+        BLOGC_TEMPLATE_CONTENT_STMT);
+    assert_null(tmp->next->next->next->next->next->next);
+    blogc_template_free_stmts(stmts);
+}
+
+
+static void
 test_template_parse_invalid_block_start(void **state)
 {
     const char *a = "{% ASD %}\n";
@@ -466,7 +542,7 @@ test_template_parse_invalid_endif_not_open(void **state)
     assert_null(stmts);
     assert_int_equal(err->type, BLOGC_ERROR_TEMPLATE_PARSER);
     assert_string_equal(err->msg,
-        "'endif' statement without an open 'ifdef' or 'ifndef' statement.\n"
+        "'endif' statement without an open 'if', 'ifdef' or 'ifndef' statement.\n"
         "Error occurred near line 1, position 28: "
         "{% block listing %}{% endif %}{% endblock %}");
     blogc_error_free(err);
@@ -709,6 +785,62 @@ test_template_parse_invalid_if_operand3(void **state)
 
 
 static void
+test_template_parse_invalid_else1(void **state)
+{
+    const char *a = "{% else %}\n";
+    blogc_error_t *err = NULL;
+    sb_slist_t *stmts = blogc_template_parse(a, strlen(a), &err);
+    assert_non_null(err);
+    assert_null(stmts);
+    assert_int_equal(err->type, BLOGC_ERROR_TEMPLATE_PARSER);
+    assert_string_equal(err->msg,
+        "'else' statement without an open 'if', 'ifdef' or 'ifndef' statement.\n"
+        "Error occurred near line 1, position 8: {% else %}");
+    blogc_error_free(err);
+}
+
+
+static void
+test_template_parse_invalid_else2(void **state)
+{
+    const char *a = "{% if BOLA == \"123\" %}{% if GUDA == \"1\" %}{% else %}{% else %}\n";
+    blogc_error_t *err = NULL;
+    sb_slist_t *stmts = blogc_template_parse(a, strlen(a), &err);
+    assert_non_null(err);
+    assert_null(stmts);
+    assert_int_equal(err->type, BLOGC_ERROR_TEMPLATE_PARSER);
+    assert_string_equal(err->msg,
+        "More than one 'else' statement for an open 'if', 'ifdef' or 'ifndef' "
+        "statement.\nError occurred near line 1, position 60: {% if BOLA == \"123\" "
+        "%}{% if GUDA == \"1\" %}{% else %}{% else %}");
+    blogc_error_free(err);
+}
+
+
+static void
+test_template_parse_invalid_else3(void **state)
+{
+    const char *a =
+        "{% if BOLA == \"123\" %}\n"
+        "{% if GUDA == \"1\" %}\n"
+        "{% else %}\n"
+        "asd\n"
+        "{% endif %}\n"
+        "{% else %}\n"
+        "{% else %}\n";
+    blogc_error_t *err = NULL;
+    sb_slist_t *stmts = blogc_template_parse(a, strlen(a), &err);
+    assert_non_null(err);
+    assert_null(stmts);
+    assert_int_equal(err->type, BLOGC_ERROR_TEMPLATE_PARSER);
+    assert_string_equal(err->msg,
+        "More than one 'else' statement for an open 'if', 'ifdef' or 'ifndef' "
+        "statement.\nError occurred near line 7, position 8: {% else %}");
+    blogc_error_free(err);
+}
+
+
+static void
 test_template_parse_invalid_block_end(void **state)
 {
     const char *a = "{% block entry }}\n";
@@ -876,6 +1008,7 @@ main(void)
         unit_test(test_template_parse_crlf),
         unit_test(test_template_parse_html),
         unit_test(test_template_parse_ifdef_and_var_outside_block),
+        unit_test(test_template_parse_nested_else),
         unit_test(test_template_parse_invalid_block_start),
         unit_test(test_template_parse_invalid_block_nested),
         unit_test(test_template_parse_invalid_foreach_nested),
@@ -895,6 +1028,9 @@ main(void)
         unit_test(test_template_parse_invalid_if_operand),
         unit_test(test_template_parse_invalid_if_operand2),
         unit_test(test_template_parse_invalid_if_operand3),
+        unit_test(test_template_parse_invalid_else1),
+        unit_test(test_template_parse_invalid_else2),
+        unit_test(test_template_parse_invalid_else3),
         unit_test(test_template_parse_invalid_block_end),
         unit_test(test_template_parse_invalid_variable_name),
         unit_test(test_template_parse_invalid_variable_name2),