Unit tests for flowgraph pretty printing.

Each test works by rendering the flowgraph for the last identified
block we see in expanded pretty-printed output, and comparing it (via
`diff`) against a checked in "foo.dot-expected.dot" file.

Each test post-processes the output to remove NodeIds ` (id=NUM)` so
that the expected output is somewhat stable (or at least independent
of how we assign NodeIds) and easier for a human to interpret when
looking at the expected output file itself.

----

Test writing style notes:

I usually tried to write the tests in a way that would avoid duplicate
labels in the output rendered flow graph, when possible.

The tests that have string literals "unreachable" in the program text
are deliberately written that way to remind the reader that the
unreachable nodes in the resulting graph are not an error in the
control flow computation, but rather a natural consequence of its
construction.

Author: pnkfelix

src/test/run-make/graphviz-flowgraph/Makefile

@@ -0,0 +1,37 @@
+-include ../tools.mk
+
+FILES=f00.rs f01.rs f02.rs f03.rs f04.rs f05.rs f06.rs f07.rs \
+      f08.rs f09.rs f10.rs f11.rs f12.rs f13.rs f14.rs f15.rs \
+      f16.rs f17.rs f18.rs f19.rs f20.rs f21.rs f22.rs
+
+
+# all: $(patsubst %.rs,$(TMPDIR)/%.dot,$(FILES)) $(patsubst %.rs,$(TMPDIR)/%.pp,$(FILES))
+all: $(patsubst %.rs,$(TMPDIR)/%.check,$(FILES))
+
+
+RUSTC_LIB=$(RUSTC) --crate-type=lib
+
+define FIND_LAST_BLOCK
+LASTBLOCKNUM_$(1) := $(shell $(RUSTC_LIB) --pretty=expanded,identified $(1) \
+			 | grep block
+			 | tail -1
+			 | sed -e 's@.*/\* block \([0-9]*\) \*/.*@\1@')
+endef
+
+ifeq ($(findstring rustc,$(RUSTC)),)
+$(error Must set RUSTC)
+endif
+
+$(TMPDIR)/%.pp: %.rs
+	$(RUSTC_LIB) --pretty=expanded,identified $< -o $@
+
+$(TMPDIR)/%.dot: %.rs
+	$(eval $(call FIND_LAST_BLOCK,$<))
+	$(RUSTC_LIB) --pretty flowgraph=$(LASTBLOCKNUM_$<) $< -o $@.tmp
+	cat $@.tmp | sed -e 's@ (id=[0-9]*)@@g' \
+                         -e 's@\[label=""\]@@' \
+                         -e 's@digraph [a-zA-Z0-9_]* @digraph block @' \
+                     > $@
+
+$(TMPDIR)/%.check: %.rs $(TMPDIR)/%.dot
+	diff -u $(patsubst %.rs,$(TMPDIR)/%.dot,$<) $(patsubst %.rs,%.dot-expected.dot,$<)

src/test/run-make/graphviz-flowgraph/f00.dot-expected.dot

@@ -0,0 +1,7 @@
+digraph block {
+    N0[label="entry"];
+    N1[label="exit"];
+    N2[label="block { }"];
+    N0 -> N2;
+    N2 -> N1;
+}

src/test/run-make/graphviz-flowgraph/f00.rs

@@ -0,0 +1,13 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub fn empty_0() {
+
+}

src/test/run-make/graphviz-flowgraph/f01.dot-expected.dot

@@ -0,0 +1,9 @@
+digraph block {
+    N0[label="entry"];
+    N1[label="exit"];
+    N2[label="expr 1"];
+    N3[label="block { 1; }"];
+    N0 -> N2;
+    N2 -> N3;
+    N3 -> N1;
+}

src/test/run-make/graphviz-flowgraph/f01.rs

@@ -0,0 +1,13 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub fn lit_1() {
+    1;
+}

src/test/run-make/graphviz-flowgraph/f02.dot-expected.dot

@@ -0,0 +1,9 @@
+digraph block {
+    N0[label="entry"];
+    N1[label="exit"];
+    N2[label="local _x"];
+    N3[label="block { let _x: int; }"];
+    N0 -> N2;
+    N2 -> N3;
+    N3 -> N1;
+}

src/test/run-make/graphviz-flowgraph/f02.rs

@@ -0,0 +1,13 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub fn decl_x_2() {
+    let _x : int;
+}

src/test/run-make/graphviz-flowgraph/f03.dot-expected.dot

@@ -0,0 +1,13 @@
+digraph block {
+    N0[label="entry"];
+    N1[label="exit"];
+    N2[label="expr 3"];
+    N3[label="expr 33"];
+    N4[label="expr 3 + 33"];
+    N5[label="block { 3 + 33; }"];
+    N0 -> N2;
+    N2 -> N3;
+    N3 -> N4;
+    N4 -> N5;
+    N5 -> N1;
+}

src/test/run-make/graphviz-flowgraph/f03.rs

@@ -0,0 +1,13 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub fn expr_add_3() {
+    3 + 33;
+}

src/test/run-make/graphviz-flowgraph/f04.dot-expected.dot

@@ -0,0 +1,11 @@
+digraph block {
+    N0[label="entry"];
+    N1[label="exit"];
+    N2[label="expr 4"];
+    N3[label="local _x"];
+    N4[label="block { let _x = 4; }"];
+    N0 -> N2;
+    N2 -> N3;
+    N3 -> N4;
+    N4 -> N1;
+}

src/test/run-make/graphviz-flowgraph/f04.rs

@@ -0,0 +1,13 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub fn pat_id_4() {
+    let _x = 4;
+}

src/test/run-make/graphviz-flowgraph/f05.dot-expected.dot

@@ -0,0 +1,19 @@
+digraph block {
+    N0[label="entry"];
+    N1[label="exit"];
+    N2[label="expr 5"];
+    N3[label="expr 55"];
+    N4[label="expr (5, 55)"];
+    N5[label="local _x"];
+    N6[label="local _y"];
+    N7[label="pat (_x, _y)"];
+    N8[label="block { let (_x, _y) = (5, 55); }"];
+    N0 -> N2;
+    N2 -> N3;
+    N3 -> N4;
+    N4 -> N5;
+    N5 -> N6;
+    N6 -> N7;
+    N7 -> N8;
+    N8 -> N1;
+}

src/test/run-make/graphviz-flowgraph/f05.rs

@@ -0,0 +1,13 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub fn pat_tup_5() {
+    let (_x, _y) = (5, 55);
+}

src/test/run-make/graphviz-flowgraph/f06.dot-expected.dot

@@ -0,0 +1,15 @@
+digraph block {
+    N0[label="entry"];
+    N1[label="exit"];
+    N2[label="expr 6"];
+    N3[label="expr S6{val: 6,}"];
+    N4[label="local _x"];
+    N5[label="pat S6{val: _x}"];
+    N6[label="block { let S6{val: _x} = S6{val: 6,}; }"];
+    N0 -> N2;
+    N2 -> N3;
+    N3 -> N4;
+    N4 -> N5;
+    N5 -> N6;
+    N6 -> N1;
+}

src/test/run-make/graphviz-flowgraph/f06.rs

@@ -0,0 +1,14 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+struct S6 { val: int }
+pub fn pat_struct_6() {
+    let S6 { val: _x } = S6{ val: 6 };
+}

src/test/run-make/graphviz-flowgraph/f07.dot-expected.dot

@@ -0,0 +1,33 @@
+digraph block {
+    N0[label="entry"];
+    N1[label="exit"];
+    N2[label="expr 7"];
+    N3[label="expr 77"];
+    N4[label="expr 777"];
+    N5[label="expr 7777"];
+    N6[label="expr [7, 77, 777, 7777]"];
+    N7[label="expr match [7, 77, 777, 7777] { [x, y, ..] => x + y }"];
+    N8[label="local x"];
+    N9[label="local y"];
+    N10[label="pat .."];
+    N11[label="pat [x, y, ..]"];
+    N12[label="expr x"];
+    N13[label="expr y"];
+    N14[label="expr x + y"];
+    N15[label="block { match [7, 77, 777, 7777] { [x, y, ..] => x + y }; }"];
+    N0 -> N2;
+    N2 -> N3;
+    N3 -> N4;
+    N4 -> N5;
+    N5 -> N6;
+    N6 -> N8;
+    N8 -> N9;
+    N9 -> N10;
+    N10 -> N11;
+    N11 -> N12;
+    N12 -> N13;
+    N13 -> N14;
+    N14 -> N7;
+    N7 -> N15;
+    N15 -> N1;
+}

src/test/run-make/graphviz-flowgraph/f07.rs

@@ -0,0 +1,15 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub fn pat_vec_7() {
+    match [7, 77, 777, 7777] {
+        [x, y, ..] => x + y
+    };
+}

src/test/run-make/graphviz-flowgraph/f08.dot-expected.dot

@@ -0,0 +1,30 @@
+digraph block {
+    N0[label="entry"];
+    N1[label="exit"];
+    N2[label="expr 8"];
+    N3[label="local x"];
+    N4[label="local _y"];
+    N5[label="expr x"];
+    N6[label="expr 88"];
+    N7[label="expr x > 88"];
+    N8[label="expr 888"];
+    N9[label="expr _y"];
+    N10[label="expr _y = 888"];
+    N11[label="block { _y = 888; }"];
+    N12[label="expr if x > 88 { _y = 888; }"];
+    N13[label="block { let x = 8; let _y; if x > 88 { _y = 888; } }"];
+    N0 -> N2;
+    N2 -> N3;
+    N3 -> N4;
+    N4 -> N5;
+    N5 -> N6;
+    N6 -> N7;
+    N7 -> N8;
+    N8 -> N9;
+    N9 -> N10;
+    N10 -> N11;
+    N7 -> N12;
+    N11 -> N12;
+    N12 -> N13;
+    N13 -> N1;
+}

src/test/run-make/graphviz-flowgraph/f08.rs

@@ -0,0 +1,16 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub fn expr_if_onearm_8() {
+    let x = 8; let _y;
+    if x > 88 {
+        _y = 888;
+    }
+}

src/test/run-make/graphviz-flowgraph/f09.dot-expected.dot

@@ -0,0 +1,44 @@
+digraph block {
+    N0[label="entry"];
+    N1[label="exit"];
+    N2[label="expr 91"];
+    N3[label="local x"];
+    N4[label="local _y"];
+    N5[label="expr x"];
+    N6[label="expr 92"];
+    N7[label="expr x > 92"];
+    N8[label="expr 93"];
+    N9[label="expr _y"];
+    N10[label="expr _y = 93"];
+    N11[label="block { _y = 93; }"];
+    N12[label="expr 94"];
+    N13[label="expr 95"];
+    N14[label="expr 94 + 95"];
+    N15[label="expr _y"];
+    N16[label="expr _y = 94 + 95"];
+    N17[label="block { _y = 94 + 95; }"];
+    N18[label="expr { _y = 94 + 95; }"];
+    N19[label="expr if x > 92 { _y = 93; } else { _y = 94 + 95; }"];
+    N20[label="block { let x = 91; let _y; if x > 92 { _y = 93; } else { _y = 94 + 95; } }"];
+    N0 -> N2;
+    N2 -> N3;
+    N3 -> N4;
+    N4 -> N5;
+    N5 -> N6;
+    N6 -> N7;
+    N7 -> N8;
+    N8 -> N9;
+    N9 -> N10;
+    N10 -> N11;
+    N7 -> N12;
+    N12 -> N13;
+    N13 -> N14;
+    N14 -> N15;
+    N15 -> N16;
+    N16 -> N17;
+    N17 -> N18;
+    N11 -> N19;
+    N18 -> N19;
+    N19 -> N20;
+    N20 -> N1;
+}

src/test/run-make/graphviz-flowgraph/f09.rs

@@ -0,0 +1,18 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub fn expr_if_twoarm_9() {
+    let x = 91; let _y;
+    if x > 92 {
+        _y = 93;
+    } else {
+        _y = 94+95;
+    }
+}